Electrophoresis via MedWorm.com MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Electrophoresis' source. Mon, 06 Feb 2012 13:31:40 +0100 A facile electrophoretic technique to monitor phosphoenolpyruvate‐dependent kinases http://www.medworm.com/index.php?rid=5656167&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100517 Phosphoenolpyruvate (PEP)‐dependent kinases are central to numerous metabolic processes and mediate the production of adenosine triphosphate (ATP) by substrate‐level phosphorylation (SLP). While pyruvate kinase (PK, EC: 2.7.1.40), the final enzyme of the glycolytic pathway is critical in the anaerobic synthesis of ATP from ADP, pyruvate phosphate dikinase (PPDK, EC: 2.7.9.1) and phosphoenolpyruvate synthase (PEPS, EC: 2.7.9.2) help generate ATP from AMP coupled to PEP as a substrate. Here we demonstrate an inexpensive and effective electrophoretic technology to determine the activities of these enzymes by blue‐native polyacrylamide gel electrophoresis (BN‐PAGE). The generation of pyruvate is linked to exogenous lactate dehydrogenase (LDH), and the oxidation of reduced nicotinamide ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5656167 Fri, 03 Feb 2012 05:00:00 +0100 5656167 Microchip electrophoresis coupled with on‐line magnetic separation and chemiluminescence detection for multiplexed immunoassay http://www.medworm.com/index.php?rid=5656166&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100543 A facile and universal strategy for multiplexed immunoassay is proposed. The strategy is based on microchip electrophoresis (MCE) coupled with on‐line magnetic separation and chemiluminescence detection. The system consisted of a microchip, an electromagnet and a photomultiplier. The realization of multiplexed immunoassay protocol involves sampling magnetic nanoparticles (MNPs) labeled antibodies, N‐(4‐aminobutyl)‐N‐ethyl‐isoluminol (ABEI) labeled antigens and free antigens in the precolumn reactor, on‐line immunoreaction, capturing the MNPs‐ immunocomplexes, and the separation of unconjugated ABEI‐labeled antigens. After on‐line magnetic separation, the free ABEI‐labeled antigens were transported into the separation channel, and mixed with hydrogen peroxide (H2O2) in... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5656166 Fri, 03 Feb 2012 05:00:00 +0100 5656166 Electroosmotic flow modulation in capillary electrophoresis by organic cations from ionic liquids http://www.medworm.com/index.php?rid=5656170&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100486 This paper describes the ability of several ionic liquids’ cations for electroosmotic flow modulation in capillary electrophoresis. Organic salts based on phosphonium, sulfonium, cysteinium, ammonium and guanidinium cations were selected to study this property. In addition, the synergistic effect of these compounds in cyclodextrin chiral separation was also evaluated. In comparison with most studied imidazolium based ionic liquids, several of the cations studied, are stronger modifiers in terms of EOF modulation. Phosphonium based compounds and tri‐octyl methylammonium chloride ([Aliquat]Cl) had the strongest ability to reverse EOF both in acidic and in basic conditions and had the lowest EOF reversal concentrations in the presence of hydroxypropyl‐β‐cyclodextrin. EOF modulation a... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5656170 Wed, 01 Feb 2012 05:00:00 +0100 5656170 Separation principles of Cycling Temperature Capillary Electrophoresis http://www.medworm.com/index.php?rid=5656169&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100550 High throughput means to detect and quantify low frequency mutations (<10−2) in the DNA coding sequences of human tissues and pathological lesions are required to discover the kinds, numbers and rates of genetic mutations that (a.) confer inherited risk for disease or (b.) arise in somatic tissues as events required for clonal diseases such as cancers and atherosclerotic plaque. While throughput of linear DNA sequencing methods have increased dramatically such methods are limited by high error rates (>10−3) rendering them unsuitable for the detection of low frequency risk‐conferring mutations among the many neutral mutations carried in the general population or created in tissue growth and development. In contrast, constant denaturing capillary electrophoresis (CDCE) coupled wi... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5656169 Wed, 01 Feb 2012 05:00:00 +0100 5656169 An improved silver stain for the visualization of lipopolysaccharides on polyacrylamide gels http://www.medworm.com/index.php?rid=5656168&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100492 In this study, the most commonly used formaldehyde‐based LPS silver stain, which has potential hazard to the health of operator, is replaced by ascorbic acid (Vc) in alkaline sodium thiosulfate solution. It takes only about 35 min to complete all the protocol, with a detection limit of 4 ng of total LPS. The results indicate that this user‐friendly method could be a good choice for LPS visualization on polyacrylamide gels. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5656168 Wed, 01 Feb 2012 05:00:00 +0100 5656168 Capillary electrophoretic analysis of whole blood samples for hemoglobin based oxygen carriers without the use of immunoprecipitation http://www.medworm.com/index.php?rid=5656165&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100506 Hemoglobin based oxygen carriers (HBOCs) are blood substitutes, synthesized by polymerizing hemoglobin, which are being developed and investigated as alternatives to blood for medical purposes. However, due to their ability to increase the oxygen carrying capacity when taken by healthy individuals, HBOCs have been used as a doping agent among endurance athletes and are included in the World Anti‐Doping Agency's Prohibited List. To maintain the fairness of competitions and continue the battle against doping it is essential to be able to detect HBOCs if present in an athlete's blood. To achieve this goal it is necessary to differentiate HBOCs from the native hemoglobin and to do so in a cost and time effective manner. We have developed a rapid capillary zone electrophoresis (CZE), UV absor... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5656165 Wed, 01 Feb 2012 05:00:00 +0100 5656165 A chemometric approach for the elucidation of the parameter impact in the hyphenation of Field Enhanced Sample Injection and Sweeping in Capillary Electrophoresis http://www.medworm.com/index.php?rid=5643640&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100483 The aim of this work was to elucidate the impacts of parameters influencing Cation Selective Exhaustive Injection coupled to sweeping and micellar electrokinetic chromatography (MEKC). A chemometric approach using cationic compounds, acidic conditions (phosphate buffer, pH 2.3) and polyacrylamide‐coated capillaries to suppress EOF were used. It was demonstrated the water plug was not useful because of long electrokinetic injections. If conductivity of the HCB and the HCB to sample conductivity ratio are sufficiently high (> 1.66 S/m and > 30, respectively), variations of HCB conductivity do not impact sensitivity. The length of the HCB must be long enough so that the most mobile cation remains stacked in this zone for a given injection time. SDS concentration should be the highe... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5643640 Tue, 31 Jan 2012 11:33:43 +0100 5643640 Bi‐directional flow induced by an AC electroosmotic micropump with DC voltage bias http://www.medworm.com/index.php?rid=5643644&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100544 This paper discusses the principle of biased Alternating Current electroosmosis (ACEO) and its application to move the bulk fluid in a micro‐channel, as an alternative to mechanical pumping methods. Previous EO driven flow research has looked at the effect of electrode asymmetry and transverse traveling wave forms on the performance of electroosmotic pumps. This paper presents an analysis that was conducted to assess the effect of combining an AC signal with a DC (Direct Current) bias when generating the electric field needed to impart electroosmosis within a micro‐channel. The results presented here are numerical and experimental. The numerical results were generated through simulations performed using COMSOL 3.5a. Currently available theoretical models for EO flows were embedded in t... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5643644 Tue, 31 Jan 2012 05:00:00 +0100 5643644 Proteomic investigation of anti‐tumor activities exerted by sinularin against A2058 melanoma cells http://www.medworm.com/index.php?rid=5643643&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100462 The extracts from soft corals have been increasingly investigated for biomedical and therapeutic purposes. The aim of this study is to examine and analyze the anti‐tumor effects of the genus Sinularia extract sinularin on A2058 melanoma cells using MTT assay, cell migration assay, wound healing assay, flow cytometric analysis and proteomic analysis. Sinularin dose‐dependently (1∼5 μg/mL) inhibited melanoma cell proliferation while the treatment at identical concentrations suppressed cell migration. Sinularin dose‐dependently enhanced apoptotic melanoma cells and caused tumor cell accumulation at G2/M phase, indicating that sinularin exerts apoptosis‐induced and cell cycle‐delayed activities in A2058 melanoma cells. Comparative proteomic analysis was conducted to investigate th... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5643643 Tue, 31 Jan 2012 05:00:00 +0100 5643643 A comparative survey of proteins from recalcitrant tissues of a non‐model gymnosperm, Douglas‐fir http://www.medworm.com/index.php?rid=5643642&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100526 In this study, we present a complete procedure detailing protein sample preparation, separation, and proteomic analysis based on cross‐species identification of Douglas‐fir. Proteins from the cambial zone, mature needles, and in‐vitro callus were extracted, purified and separated via 1D and 2D SDS‐PAGE. One dimensional electrophoresis coupled with ESI‐MS/MS was used for cross‐species protein identification in order to evaluate the potential of this approach and reveal major differences in protein profiles among tested tissues. Identified proteins were functionally and developmentally compared. The likely contribution of these proteins to the properties of the cell wall and wood is indicated and discussed. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5643642 Tue, 31 Jan 2012 05:00:00 +0100 5643642 High performance capillary electrophoretic separation of double‐stranded oligonucleotides using a poly(ethylpyrrolidine methacrylate‐co‐methyl methacrylate) coated capillary http://www.medworm.com/index.php?rid=5643641&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100514 Here we describe a capillary electrophoretic method for the separation of double‐stranded oligonucleotides (ds‐ODNs) ranging from 16 ‐ 20 bp with 2 base pair resolution using a low concentration of poly(ethylpyrrolidine methacrylate‐co‐methyl methacrylate) (PEPyM‐co‐PMMA) copolymer physically adsorbed to a capillary surface. Contrary to traditional DNA separations we show that the ds‐ODN with the highest molecular size eluted first and propose that this phenomena is due to a screening effect by the PEPyM‐co‐PMMA coating on the smaller ds‐ODNs negative charge during elution. Key to the performance of this separation was a sample preparation time of less than 1 h and analysis time of 40 min. Repeatability of intra‐day migration time for the mixtures was typically <... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5643641 Tue, 31 Jan 2012 05:00:00 +0100 5643641 Meetings Diary http://www.medworm.com/index.php?rid=5635148&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201290009 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635148 Fri, 27 Jan 2012 18:27:50 +0100 5635148 Call for Papers http://www.medworm.com/index.php?rid=5635147&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201290007 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635147 Fri, 27 Jan 2012 18:27:49 +0100 5635147 Investigation of in‐line solid‐phase extraction capillary electrophoresis for the analysis of drugs of abuse and their metabolites in water samples http://www.medworm.com/index.php?rid=5635146&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100199 In this study, in‐line solid‐phase extraction (SPE) was used as an enrichment technique in combination with CE for the preconcentration and separation of 2‐ethylidene‐1,5‐dimethyl‐3,3‐diphenylpyrrolidine (EDDP), cocaine (COC), codeine (COD) and 6‐acetylmorphine (6AM). The separation buffer (BGE) used was 80 mM disodium phosphate anhydrous and 6 mM of HCl (final BGE pH of 3). The SPE extractor consists of a small segment of capillary filled with Oasis HLB sorbent and inserted into the inlet section of the electrophoretic capillary. Different parameters affecting preconcentration were evaluated, such as sample pH, the volume of the elution plug and sample injection time. The detection limits (LODs) reached for standard samples by in‐line SPE‐CE‐UV ranged between 50 ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635146 Fri, 27 Jan 2012 18:27:46 +0100 5635146 Mechanism of change in enantiomer migration order of enantioseparation of tartaric acid by ligand exchange capillary electrophoresis with Cu(II) and Ni(II)–D‐quinic acid systems http://www.medworm.com/index.php?rid=5635145&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100512 AbstractThe mechanism of change in the enantiomer migration order (EMO) of tartarate on ligand exchange CE with Cu(II)– and Ni(II)–D‐quinic acid systems was investigated thoroughly by circular dichroism (CD) spectropolarimetry. The 13C NMR spectra of solutions containing D‐quinate (pH 5.0) with Cu(II) or Ni(II) revealed the coordination of carboxylate and hydroxyl groups on D‐quinate. The D‐quinic acid concentration dependence of the CD spectra at a fixed Cu(II) concentration at pH 5.0 indicates that the 1:1, 1:2 and 1:3 Cu(II)–D‐quinate complexes were formed with an increase in the concentration of D‐quinic acid. The CD spectral behavior revealed that D‐tartarate is selectively coordinated to the 1:1 complex to give the 1:1:1 Cu(II)–D‐quinate–D‐tartarate ternar... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635145 Fri, 27 Jan 2012 18:27:45 +0100 5635145 Electromembrane extraction combined with cyclodextrin‐modified capillary electrophoresis for the quantification of trimipramine enantiomers http://www.medworm.com/index.php?rid=5635144&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100426 AbstractA sensitive, simple and reproducible method was developed for preconcentration and determination of trimipramine (TPM) enantiomers in biological samples using electromembrane extraction combined with cyclodextrin‐modified capillary electrophoresis (CE). During the extraction, TPM enantiomers migrated from a 5 mL sample solution through a thin layer of 2‐nitrophenyl octyl ether NPOE immobilized in the pores of a hollow fiber, and into a 20 μL acidic aqueous acceptor phase presented inside the lumen of the fiber. A Box–Behnken design and the response surface methodology (RSM) were used for the optimization of different variables on extraction efficiency. Optimized extraction conditions were: NPOE as supported liquid membrane, inter‐electrode distance of 5 mm, stirring ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635144 Fri, 27 Jan 2012 18:27:43 +0100 5635144 Mutation scanning‐based analysis of anisakid larvae from Sillago flindersi from Bass Strait, Australia http://www.medworm.com/index.php?rid=5635143&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100438 This study revealed that 92% of the S. flindersi examined were infected with anisakids (n=194), which were represented by seven genotypes. Phylogenetic analyses of the genotypes defined herein, together with reference sequence for Anisakis pegreffii and Hysterothylacium sp. from public databases (i.e. GenBank), revealed the presence of A. pegreffii (n=24), Hysterothylacium larval type IV (n=90) and Hysterothylacium larval type VIII (n=80) in S. flindersi. Thus, the PCR‐coupled mutation scanning approach employed herein is an effective tool for the genetic characterisation of anisakid nematodes for diagnostic and analytical purposes (nucleotide sequences reported in this paper are available in the GenBank database under accession nos. JN631796‐809). (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635143 Fri, 27 Jan 2012 18:27:42 +0100 5635143 Arbitrary single primer amplification of trace DNA substrates yields sequence content profiles that are discriminatory and reproducible http://www.medworm.com/index.php?rid=5635142&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100359 AbstractSingle primer amplification is shown to yield a DNA profile that is reproducible when based on the sequence content of the amplicons rather than on the pattern of length polymorphism. The sequence‐based profile increases in reliability with increasing numbers of cycles of amplification. This process uses an arbitrarily chosen primer and a low initial annealing temperature in order to amplify sequences from the whole metagenome present in a sample that may contain only trace DNA, and a large number of cycles to select subsets of sequences based on variable amplification efficiency. Using arrays, we demonstrate the utility and limitations of this approach for profiling the large metagenomes typical of soils and the trace DNA present in drug seizures. We suggest that this type of pr... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635142 Fri, 27 Jan 2012 18:27:40 +0100 5635142 Carotid atherosclerotic plaques: Proteomics study after a low‐abundance protein enrichment step http://www.medworm.com/index.php?rid=5635141&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100395 AbstractAtherosclerosis is one of the most important causes of cardiovascular and cerebrovascular events. Although phenotypic differentiation between stable and unstable plaques is currently possible, proteomic analysis of the atherosclerotic plaque could offer a global view of the atherosclerosis pathology. With the objective to highlight the detection of low‐abundance proteins, we reduced the dynamic range of proteins by combinatorial peptide ligand library treatment of human carotid artery atherosclerotic plaques. After enrichment step, abundance of major proteins was decreased, revealing different protein profiles as assessed by both SDS‐polyacrylamide gel electrophoresis and two‐dimensional electrophoresis comparative analyses. Identification of proteins that were contained in a... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635141 Fri, 27 Jan 2012 18:27:38 +0100 5635141 Proteomics of cypress pollen allergens using double and triple one‐dimensional electrophoresis http://www.medworm.com/index.php?rid=5635140&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100324 AbstractItalian cypress (Cupressus sempervirens, Cups) pollen causes allergic diseases in inhabitants of many of the cities surrounding the Mediterranean basin. However, allergens of Cups pollen are still poorly known. We introduce here a novel proteomic approach based on double one‐dimensional gel electrophoresis (D1‐DE) as an alternative to the 2‐DE immunoblot, for the specific IgE screening of allergenic proteins from pollen extracts. The sequential one‐dimensional combination of IEF and SDS‐PAGE associated with IgE immunoblotting allows a versatile multiplexed immunochemical analysis of selected groups of allergens by converting a single protein spot into an extended protein band. Moreover, the method appears to be valuable for MS/MS identification, without protein purificati... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635140 Fri, 27 Jan 2012 18:27:37 +0100 5635140 Stability of amyloid‐β peptides in plasma and serum http://www.medworm.com/index.php?rid=5635139&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100455 In conclusion, plasma may be more appropriate than serum for analysing Aβ peptides for routine application. At least, the analysis should be done within 24 h and peptide ratios should be created to minimise artificial results. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635139 Fri, 27 Jan 2012 18:27:34 +0100 5635139 Analytical solutions and validation of electric field and dielectrophoretic force in a bio‐microfluidic channel http://www.medworm.com/index.php?rid=5635138&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100325 AbstractIn a microbiological device, cell or particle manipulation and characterization require the use of electric field on different electrodes in several configurations and shapes. To efficiently design microelectrodes within a microfluidic channel for dielectrophoresis focusing, manipulation and characterization of cells, the designer will seek the exact distribution of the electric potential, electric field and hence dielectrophoresis force exerted on the cell within the microdevice. In this paper we describe the approach attaining the analytical solution of the dielectrophoretic force expression within a microchannel with parallel facing same size electrodes present on the two faces of channel substrates, with opposite voltages on the pair electrodes. Simple Fourier series mathematic... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635138 Fri, 27 Jan 2012 18:27:31 +0100 5635138 Contents – Electrophoresis 3'2012 http://www.medworm.com/index.php?rid=5635137&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201290010 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635137 Fri, 27 Jan 2012 18:27:27 +0100 5635137 Editorial Board: Electrophoresis 3'2012 http://www.medworm.com/index.php?rid=5635136&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201290008 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635136 Fri, 27 Jan 2012 18:27:26 +0100 5635136 Cover Picture: Electrophoresis 3'2012 http://www.medworm.com/index.php?rid=5635135&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201290006 AbstractIssue no. 3 is a regular issue consisting of 17 contributions distributed over 5 separate parts. The issue starts with 4 research articles on micro‐ and nanofluidics making up Part I. This is followed by Part II that has 5 research articles involving studies on proteins, peptides and proteomics. Part III has 3 contributions dealing with studies on nucleic acids. Part IV has 3 research articles on enantioseparation methodologies. The last part (Part V) consists of 2 contributions on various aspects of preconcentration in CE of drug of abuse and their metabolites and the sensitive monitoring for ribonucleotide reductase activity. This issue, with as few as 17 contributions, is rich in very important ideas in the field for further investigations.Featured articles include:Modeling of... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5635135 Fri, 27 Jan 2012 18:27:24 +0100 5635135 Proteomics analysis of in vitro protein methylation during Src‐induced transformation http://www.medworm.com/index.php?rid=5576489&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100280 In this study, we determined if protein methylation was involved in Src activation and which methylated proteins were associated with this activity. Using in vitro methylation and 2‐DE analysis of viral Src (v‐Src)‐transformed rat kidney epithelial cells (RK3E), several known and novel methylated proteins were identified based on their changes in methylation signal intensity upon transformation. Among these, elongation factor 2 (EF‐2), heterogeneous nuclear ribonucleoprotein K (hnRNP K), and β‐tubulin protein expressions remained unchanged, indicating that their altered methylation levels were due to Src activation. In addition, the altered expression of β‐actin, vimentin, and protein phosphatase 2, catalytic subunit (PPP2C) as well as protein phosphatase 2, catalytic subunit... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5576489 Mon, 09 Jan 2012 05:00:00 +0100 5576489 A homogeneous assay for protein analysis in droplets by fluorescence polarization http://www.medworm.com/index.php?rid=5576488&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100350 We present a novel homogeneous (“mix‐incubate‐read”) droplet microfluidic assay for specific protein detection in picoliter volumes by fluorescence polarization (FP), for the first time demonstrating the use of FP in a droplet microfluidic assay. Using an FP‐based assay we detect streptavidin concentrations as low as 500 nM and demonstrate that an FP assay allows us to distinguish droplets containing 5 μM rabbit IgG from droplets without IgG with an accuracy of 95%, levels relevant for hybridoma screening. This adds to the repertoire of droplet assay techniques a direct protein detection method which can be performed entirely inside droplets without the need for labeling of the analyte molecules. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5576488 Mon, 09 Jan 2012 05:00:00 +0100 5576488 Modeling of droplet traffic in interconnected microfluidic ladder devices http://www.medworm.com/index.php?rid=5576487&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100320 AbstractThe problem of controlling the droplet motion in multiphase flows on the microscale has gained increasing attention because the droplet‐based microfluidic devices provide great potentials for chemical and biological applications. It is critical to understand the relevant physics on droplet hydrodynamics and thus control the generation, motion, splitting, and coalescence of droplets in complex microfluidic networks. Numerical simulations using the volume of fluid algorithm are conducted to investigate the time‐dependent dynamics of droplets in gas–liquid multiphase devices. An analytical model based on the electronic–hydraulic analogy is developed to describe the hydrodynamic behavior of the droplets in interconnected microfluidic ladder devices. It is found that the pressur... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5576487 Mon, 09 Jan 2012 05:00:00 +0100 5576487 Human complement factor 3 polymorphism determination by capillary electrophoresis of serum http://www.medworm.com/index.php?rid=5576486&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100451 AbstractVariability of complement factor 3 (C3) mobility in serum protein electrophoresis was investigated. We found that the migration time of C3 can be reproducibly determined (beween‐run CV=0.76%) using clinical capillary electrophoresis (CE) equipment (the Capillarys™ 2 system, Sebia). Moreover, we found a significant difference (p<0.001) in migration times of the major C3 phenotypes FF (fast‐fast), FS (fast‐slow) and SS (slow‐slow). Glycosylation did not significantly affect test results. This is the first report on the migration time of C3 phenotypes on a clinical CE instrument. The presented method allows faster data than agarose‐electrophoresis or genotyping. Moreover, reference ranges for serum C3 concentration depend on C3 phenotype, which allows a better tailored ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5576486 Mon, 09 Jan 2012 05:00:00 +0100 5576486 Quantitative experimental determination of primer–dimer formation risk by free‐solution conjugate electrophoresis http://www.medworm.com/index.php?rid=5592633&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100452 AbstractDNA barcodes are short, unique ssDNA primers that “mark” individual biomolecules. To gain better understanding of biophysical parameters constraining primer–dimer formation between primers that incorporate barcode sequences, we have developed a capillary electrophoresis method that utilizes drag‐tag‐DNA conjugates to quantify dimerization risk between primer‐barcode pairs. Results obtained with this unique free‐solution conjugate electrophoresis approach are useful as quantitatively precise input data to parameterize computation models of dimerization risk. A set of fluorescently labeled, model primer‐barcode conjugates were designed with complementary regions of differing lengths to quantify heterodimerization as a function of temperature. Primer–dimer cases comp... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5592633 Sun, 01 Jan 2012 05:00:00 +0100 5592633 Chiral separation of Huperzine A using CE – Method validation and application in pharmaceutical formulations http://www.medworm.com/index.php?rid=5576485&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100372 AbstractThe aim of this work is the development, validation and application of an MEKC method for the chiral separation of Huperzine A. Huperzine A is an important compound that is used to treat Alzheimer's disease. However, only the (−)‐form of this compound is biologically active and behaves as a potential acetylcholinesterase inhibitor. Therefore, the separation of the (−)‐form from the (+)‐form is of greatest importance. Optimal conditions, regarding resolution and analysis time, were established by altering several experimental parameters, such as temperature, field strength, pH, type and concentration of BGE and chiral selector. A major problem that had to be solved in this study was the low intensity and efficiency of the peaks. More parameters were examined, such as the a... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5576485 Sun, 01 Jan 2012 05:00:00 +0100 5576485 Electrophoresis Acknowledgements http://www.medworm.com/index.php?rid=5568482&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201290000 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568482 Sun, 01 Jan 2012 05:00:00 +0100 5568482 Meetings Diary http://www.medworm.com/index.php?rid=5568481&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201290004 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568481 Sun, 01 Jan 2012 05:00:00 +0100 5568481 Call for Papers http://www.medworm.com/index.php?rid=5568480&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201290002 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568480 Sun, 01 Jan 2012 05:00:00 +0100 5568480 Fast investigations from biological matrices using CE – Test of a blood–brain barrier model http://www.medworm.com/index.php?rid=5568479&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100282 AbstractIn order to adopt a general workflow for complex biological matrices with respect to a new blood–brain barrier (BBB) model, a micellar electrokinetic chromatography method has been developed. The cells forming the BBB have been cultivated in a special cell growth medium in which six drugs (acetaminophen, caffeine, carbamazepine, cimetidine, indometacin and propranolol) have been dissolved and tested for their penetration properties. The results showed good to very good accordance to the reference values. Samples were directly injected onto the capillary without any pretreatment (fused silica capillary, id: 50 μm, L: 48 cm, l: 40 cm). After method development, separations were carried out using a 60 mM borate buffer containing 200 mM of SDS at 30 kV, leading to an analy... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568479 Sun, 01 Jan 2012 05:00:00 +0100 5568479 Electrophoretic separations in poly(dimethylsiloxane) microchips using a mixture of ionic and zwitterionic surfactants http://www.medworm.com/index.php?rid=5568477&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100259 AbstractThe use of mixtures of ionic and zwitterionic surfactants in poly(dimethylsiloxane) (PDMS) microchips is reported. The effect of surfactant concentration on electroosmotic flow (EOF) was studied for a single anionic surfactant (sodium dodecyl sulfate, SDS), a single zwitterionic surfactant (N‐tetradecylammonium‐N,N‐dimethyl‐3‐ammonio‐1‐propanesulfonate, TDAPS), and a mixed SDS/TDAPS surfactant system. SDS increased the EOF as reported previously while TDAPS showed an initial increase in EOF followed by a reduction at higher concentrations. When TDAPS was added to a solution containing SDS, the EOF decreased in a concentration‐dependent manner. The EOF for all three surfactant systems followed expected pH trends, with increasing EOF at higher pH. The mixed surfactant... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568477 Sun, 01 Jan 2012 05:00:00 +0100 5568477 Poly(ethylene glycol)‐coated microfluidic devices for chip electrophoresis http://www.medworm.com/index.php?rid=5568476&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100401 AbstractHerein, we report on a strategy for durable modification of the channel surface in microfluidic glass chips with the neutral hydrophilic‐coating material poly(ethylene glycol) PEG‐1M‐100. Applied in microchip electrophoresis such PEG‐coated devices exhibit a suppressed electroosmotic flow and reduced analyte adsorption. The PEG‐coated chips were successfully applied in chip electrophoresis of FITC‐labelled amines and amino acids and native proteins as well as in chiral separations. The performance of the coated chips was found to be superior compared with uncoated microchips. The coated chips exhibited high stability and the relative standard deviation of migration times in PEG‐coated devices was less than 2%. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568476 Sun, 01 Jan 2012 05:00:00 +0100 5568476 Bleach gel: A simple agarose gel for analyzing RNA quality http://www.medworm.com/index.php?rid=5568475&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100335 AbstractRNA‐based applications requiring high‐quality, non‐degraded RNA are a foundational element of many research studies. As such, it is paramount that the integrity of experimental RNA is validated prior to cDNA synthesis or other downstream applications. In the absence of expensive equipment such as microfluidic electrophoretic devices, and as an alternative to the costly and time‐consuming standard formaldehyde gel, RNA quality can be quickly analyzed by adding small amounts of commercial bleach to TAE buffer‐based agarose gels prior to electrophoresis. In the presence of low concentrations of bleach, the secondary structure of RNA is denatured and potential contaminating RNases are destroyed. Because of this, the ‘bleach gel’ is a functional approach that addresses the... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568475 Sun, 01 Jan 2012 05:00:00 +0100 5568475 Agarose gel electrophoresis reveals structural fluidity of a phage T3 DNA packaging intermediate http://www.medworm.com/index.php?rid=5568474&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100326 AbstractWe find a new aspect of DNA packaging‐associated structural fluidity for phage T3 capsids. The procedure is (i) glutaraldehyde cross‐linking of in vivo DNA packaging intermediates for the stabilization of structure and then (ii) determining effective radius by two‐dimensional agarose gel electrophoresis (2D‐AGE). The intermediates are capsids with incompletely packaged DNA (ipDNA) and without an external DNA segment; these intermediates are called ipDNA‐capsids. We initially increase the production of ipDNA‐capsids by raising NaCl concentration during in vivo DNA packaging. By 2D‐AGE, we find a new state of contracted shell for some particles of one previously identified ipDNA‐capsid. The contracted shell‐state is found when the ipDNA length/mature DNA length (F) ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568474 Sun, 01 Jan 2012 05:00:00 +0100 5568474 Gold nanoparticle‐coated capillaries for protein and peptide analysis on open‐tubular capillary electrochromatography http://www.medworm.com/index.php?rid=5568473&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100297 We report a new method of immobilization of gold nanoparticles (AuNPs) on a fused‐silica capillary through covalent binding. The resulting modified capillary was applied to electrophoretic systems to improve the efficiency of separation and the selectivity of selected solutes. The immobilization of AuNPs on the capillary wall was performed in a very simple and fast way without requiring heating. The surface features of an AuNP‐coated capillary column were determined using the scanning electron microscopy. The chromatographic properties of AuNP‐coated capillaries were investigated through variation of the buffer pH and separation voltage. Effective separations of synthetic peptides mixture were obtained on the AuNP‐coated capillaries. The method shows a remarkable stability since it... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568473 Sun, 01 Jan 2012 05:00:00 +0100 5568473 Modeling and simulation of nanoparticle separation through a solid‐state nanopore http://www.medworm.com/index.php?rid=5568471&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100201 In this study, we have simulated high‐density lipoprotein (HDL) and low‐density lipoprotein (LDL) as the sample nanoparticles to demonstrate the capability of such a platform. Numerical results suggest that efficient separation of HDL from LDL in a 0.2 M KCL solution (resembling blood buffer) through a 150 nm pore is possible if the pore surface charge density is ∼ −4.0 mC/m2. Moreover, we observe that pore length and diameter are relatively less important in the nanoparticle separation process considered here. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568471 Sun, 01 Jan 2012 05:00:00 +0100 5568471 Electrophoretically driven SDS removal and protein fractionation in the shotgun analysis of membrane proteomes http://www.medworm.com/index.php?rid=5568470&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100364 AbstractSDS is mostly used to enhance the solubilization and extraction of membrane proteins due to its strong detergency and low cost. Nevertheless, SDS interferes with the subsequent procedures and needs to be removed from the samples. In this work, a special gradient gel electrophoresis (GGE) system was developed to remove SDS from the SDS‐solubilized protein samples. As a proof‐of‐principle experiment, the GGE system was designed to be composed of an agarose loading layer, six polyacrylamide fractionation layers with different concentrations and a high‐concentration polyacrylamide sealing layer. The advantages of the GGE system are that it not only can electrophoretically remove SDS efficiently so that the protein loss resulted from the repeated gel washing after electrophoresi... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568470 Sun, 01 Jan 2012 05:00:00 +0100 5568470 An insight into the abundant proteome of 46BR.1G1 fibroblasts deficient of DNA ligase I http://www.medworm.com/index.php?rid=5568469&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100332 AbstractThis work presents the proteome profile of cultured human skin fibroblasts established from a patient affected by DNA ligase I (Lig I) deficiency syndrome, a rare disorder characterized by immunodeficiency, growth retardation and sun sensitivity. 2‐DE (in the 3–10 and 4–7 pH ranges) was the separation technique used for the production of maps. MALDI‐TOF/MS and LC‐MS/MS were the mass spectrometry platforms applied for the identification of proteins in gel spots. A total of 154 proteins, including 41 never detected before in skin fibroblasts with this approach, were identified in gel spots analyzed. This newly generated extensive database provides for the first time a global picture of abundant proteins in 46BR.1G1 skin fibroblasts. While being relevant to the particular di... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568469 Sun, 01 Jan 2012 05:00:00 +0100 5568469 Systematic comparison of technical details in CBB methods and development of a sensitive GAP stain for comparative proteomic analysis http://www.medworm.com/index.php?rid=5568468&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100300 In this study, we systematically evaluated the effects of different staining parameters on CBB methods by 1‐DE and 2‐DE, and demonstrated that G‐250 was more suitable for visualizing low‐abundant proteins as well as generating more spots than R‐250, whereas R‐250 had a superior capability for quick staining of high‐abundant proteins. The staining produced by mixing G‐250 and R‐250 in different ratios showed similar sensitivity. Compared with acetic acid, phosphoric acid produced more protein spots. Ammonium‐based stain demonstrated a superior sensitivity than the aluminum‐based one. Based on these findings, a new protocol using CBB G‐250, ammonium sulfate and phosphoric acid (GAP) was developed by incorporating the fixation, sensitization and staining procedures tog... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568468 Sun, 01 Jan 2012 05:00:00 +0100 5568468 Structural changes in metallothionein isoforms revealed by capillary electrophoresis and Brdicka reaction http://www.medworm.com/index.php?rid=5568467&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100312 AbstractMetallothionein (MT) as a potential cancer marker is at the center of interest and its properties, functions and behavior under various conditions is intensively studied. In the present study, two major mammalian MT isoforms (MT‐1 and MT‐2) were separated using capillary electrophoresis (CE) coupled with UV detector in order to describe their basic behavior. Under the optimized conditions, the separation of both isoforms was enabled as well as estimation of detection limits as subunits and units of ng per μL for MT‐2 and MT‐1, respectively. Further, the effects of thermal treatment and the presence of denaturing agent such as urea on MT‐1 and MT‐2 isoforms were studied by CE‐UV. Thermal treatment caused an increase in the signals of both isoforms. A new parameter cal... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568467 Sun, 01 Jan 2012 05:00:00 +0100 5568467 Contents – Electrophoresis 2'2012 http://www.medworm.com/index.php?rid=5568465&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201290005 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568465 Sun, 01 Jan 2012 05:00:00 +0100 5568465 Editorial Board: Electrophoresis 2'2012 http://www.medworm.com/index.php?rid=5568464&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201290003 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568464 Sun, 01 Jan 2012 05:00:00 +0100 5568464 Cover Picture: Electrophoresis 2'2012 http://www.medworm.com/index.php?rid=5568463&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201290001 AbstractIssue no. 2 is a regular issue consisting of 18 contributions distributed over 5 distinct parts. The issue has an “Emphasis on Proteins and Proteomics” with 7 contributions featured in Part I. This is followed by Part II that has 4 research articles on nanopore and nanoparticles based analyses. Part III has 2 contributions on agarose gel electrophoresis for the analysis of the structure fluidity of a phage T3 DNA packaging intermediate and analyzing RNA quality. Part IV has two research articles on microchip capillary electrophoresis with poly(ethylene glycol)‐coated microfluidic devices and poly(dimethylsiloxane) microchips using a mixture of ionic and zwitterionic surfactants. The last part (Part V) consists of 3 contributions on CE of some common controlled stimulants, CE ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5568463 Sun, 01 Jan 2012 05:00:00 +0100 5568463 Meetings Diary http://www.medworm.com/index.php?rid=5549449&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190127 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5549449 Thu, 29 Dec 2011 10:48:04 +0100 5549449 Call for Papers http://www.medworm.com/index.php?rid=5549448&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190125 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5549448 Thu, 29 Dec 2011 10:48:02 +0100 5549448 Recent advances in the application of CE to forensic sciences, an update over years 2009–2011 http://www.medworm.com/index.php?rid=5549447&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100463 AbstractThe present article reviews and comments the applications of capillary electrophoresis in the different areas of forensic sciences covering the time from the second half of 2009 until the first part of 2011, being the latest update of previous reviews covering the years from 2001 to 2009. Numerous articles reporting applications of capillary electrophoresis to analytical problems of potential interest for the forensic researchers and scientists can be found in the most qualified journals of analytical chemistry, analytical biochemistry, pharmacology, toxicology, laboratory medicine, human genetics, etc. However, the present review has been focused on discussing only the most relevant examples of analytical applications of capillary electrophoretic and electrokinetic techniques publ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5549447 Thu, 29 Dec 2011 10:47:51 +0100 5549447 Recent advances in amino acid analysis by capillary electrophoresis http://www.medworm.com/index.php?rid=5549446&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100360 We present new developments in amino acid analysis with CE, which are reported describing the use of lasers or light emitting diodes for fluorescence detection, conductimetry electrochemiluminescence detectors, mass spectrometry applications, and lab‐on‐a‐chip applications using CE. In addition, we describe articles concerning clinical studies and neurochemical applications of these techniques. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5549446 Thu, 29 Dec 2011 10:47:43 +0100 5549446 The dynamicity of the Journal – moving openly to accepting more contributions on liquid‐phase separation methods http://www.medworm.com/index.php?rid=5549445&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190123 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5549445 Thu, 29 Dec 2011 10:47:41 +0100 5549445 Contents – Electrophoresis 1'2012 http://www.medworm.com/index.php?rid=5549444&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190128 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5549444 Thu, 29 Dec 2011 10:47:40 +0100 5549444 Editorial Board: Electrophoresis 1'2012 http://www.medworm.com/index.php?rid=5549443&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190126 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5549443 Thu, 29 Dec 2011 10:47:39 +0100 5549443 Cover Picture: Electrophoresis 1'2012 http://www.medworm.com/index.php?rid=5549442&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190124 AbstractIssue no. 1 is a special issue on Reviews containing 17 critical and comprehensive review articles on many timely topics in the field including CE at the omics level, CE and CEC of amino acid and peptides, liquid phase separation systems for in‐depth proteomics analysis, microfluidic surface modification, role of microchip electrophoresis in clinical analysis, forensic sciences, CE and CEC of antibiotics, food analysis and foodomics, CE and CEC of phytochemicals and natural products, CE of inorganic species, EMMA in enzymatic and derivatization reactions, enantioseparations by CE, coupling of solid phase extraction to CE, and organic monoliths for hydrophilic interaction electrochromatography, and immunoaffinity chromatography. This issue opens up the thirty third volume of the J... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5549442 Thu, 29 Dec 2011 10:47:38 +0100 5549442 Simultaneous determination of deoxycytidine diphosphate and deoxycytidine triphosphate by capillary electrophoresis with transient isotachophoretic stacking: A sensitive monitoring method for ribonucleotide reductase activity http://www.medworm.com/index.php?rid=5542092&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100474 AbstractA simple and rapid capillary electrophoretic method was developed for simultaneous determination of sub‐micromolar 2′‐deoxycytidine 5′‐diphosphate (dCDP) and 2′‐deoxycytidine 5′‐triphosphate (dCTP) levels in enzyme assays without using radioactively labeled substrates. The separation was performed at 25°C using MES in the BGE as the terminating ion, the chloride ions in the sample buffer as the leading ion, and PEG 4000 in the BGE as the EOF suppressor for sample stacking by transient isotachophoresis (tITP). Several parameters affecting the separation were investigated, including the pH of the BGE, the concentration of sodium chloride in the sample buffer, and the concentrations of MES and PEG 4000 in the running buffer. Good separation with high separation effi... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5542092 Fri, 23 Dec 2011 05:00:00 +0100 5542092 Simultaneous determination of nitrite and nitrate in human plasma by on‐capillary preconcentration with field‐amplified sample stacking http://www.medworm.com/index.php?rid=5512026&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100285 AbstractA simple method for the determination of nitrite and nitrate in human plasma has been developed using CZE with minimal sample preparation. Field‐amplified sample stacking (FASS) was used to achieve submicromolar detection by dilution of the plasma sample with deionized water. In CZE, the separation of nitrite and nitrate was achieved within 10 min without adding EOF modifier. The optimal condition was achieved with 50 mM phosphate buffer at pH 9.3. The ninefold diluted plasma samples were injected hydrodynamically for 40 s into a 60 cm×75 μm id uncoated fused‐silica capillary. The separation voltage was 20 kV (negative potential) and UV detection was performed at 214 nm. The linearity curves for nitrite and nitrate were obtained by the standard addition method. ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512026 Wed, 14 Dec 2011 05:00:00 +0100 5512026 Direct visualization of electrophoretic mobility shift assays using nanoparticle–aptamer conjugates http://www.medworm.com/index.php?rid=5512025&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100308 AbstractHere, we demonstrate that aptamers tethered to gold nanoparticles enable direct visualization of protein–oligonucleotide interactions during gel electrophoresis. This technique is used to confirm that an aptamer previously identified as binding to C‐reactive protein (CRP) only binds to the monomeric form of CRP. While native, pentameric CRP (pCRP) is used in clinical assays to predict cardiovascular disease (CVD) risk, it is the monomeric isoform that is more strongly associated with pro‐inflammatory and pro‐atherogenic effects. To visualize this selectivity, the CRP–aptamer was conjugated to streptavidin‐coated gold nanoparticles and the mobility of the free oligonucleotide–nanoparticle conjugate (ON‐NP) and the protein/ON‐NP complex bands were visualized and rec... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512025 Wed, 14 Dec 2011 05:00:00 +0100 5512025 Enantiomeric separation of some common controlled stimulants by capillary electrophoresis with contactless conductivity detection http://www.medworm.com/index.php?rid=5500903&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100370 AbstractCE methods with capacitively coupled contactless conductivity detection (C4D) were developed for the enantiomeric separation of the following stimulants: amphetamine (AP), methamphetamine (MA), ephedrine (EP), pseudoephedrine (PE), norephedrine (NE) and norpseudoephedrine (NPE). Acetic acid (pH 2.5 and 2.8) was found to be the optimal background electrolyte for the CE‐C4D system. The chiral selectors, carboxymethyl‐β‐cyclodextrin (CMBCD), heptakis(2,6‐di‐O‐methyl)‐β‐cyclodextrin (DMBCD) and chiral crown ether (+)‐(18‐crown‐6)‐2,3,11,12‐tetracarboxylic acid (18C6H4), were investigated for their enantioseparation properties in the BGE. The use of either a single or a combination of two chiral selectors was chosen to obtain optimal condition of enantiomeric... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5500903 Tue, 13 Dec 2011 05:00:00 +0100 5500903 In situ demonstration and quantitative analysis of the intrinsic properties of glycoside hydrolases http://www.medworm.com/index.php?rid=5500902&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100333 AbstractBased on digital image analysis techniques and a series of optimizations in native electrophoresis, a new direct method to simultaneously detect the intrinsic properties of each active component in the enzymatic system of glycoside hydrolase was established. The key technique is that the concentration changes of substrate (or product) on the gel can be determined quantitatively by the gray value changes of the corresponding band after electrophoretic separation. In this manner, the catalytic characteristics of each glycoside hydrolase component were demonstrated in situ and were easily determined after immersing the gel in a series of solutions containing substrates or their derivatives. Because of its high throughput, great sensitivity, and convenient operation, this method can be... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5500902 Tue, 13 Dec 2011 05:00:00 +0100 5500902 Rapid and efficient protein enzymatic digestion: An experimental comparison http://www.medworm.com/index.php?rid=5500901&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100123 This study examines the fast, efficient and low‐cost proteolytic strategies for the digestion process, and for protein identification based on the use of ultrasound and infrared technology. In addition, comparisons of the applied techniques were studied. Several differences were found, suggesting the potential use of proteolysis accelerated by infrared radiation. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5500901 Tue, 13 Dec 2011 05:00:00 +0100 5500901 Organic monoliths for hydrophilic interaction electrochromatography/chromatography and immunoaffinity chromatography http://www.medworm.com/index.php?rid=5482747&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100523 This article is aimed at providing a review of the progress made over the past decade in the preparation of polar monoliths for hydrophilic interaction LC (HILIC)/capillary electrochromatography (HI‐CEC) and in the design of immuno‐monoliths for immunoaffinity chromatography that are based on some of the polar monolith precursors used in HILIC/HI‐CEC. In addition, this review article discusses some of the applications of polar monoliths by HILIC and HI‐CEC, and the applications of immuno‐monoliths. This article is by no means an exhaustive review of the literature; it is rather a survey of the recent progress made in the field with 83 references published in the past decade on the topics of HILIC and immunoaffinity chromatography monoliths. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5482747 Wed, 07 Dec 2011 05:00:00 +0100 5482747 Recent advances in the application of capillary electromigration methods for food analysis and Foodomics http://www.medworm.com/index.php?rid=5482746&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100385 AbstractThe analysis of food components using capillary electromigration methods is reviewed in this work. Papers that were published from February 2009 to February 2011 are included following the previous review by Herrero et al. (Electrophoresis, 2010, 31, 205–228). The analysis of amino acids, biogenic amines, peptides, proteins, DNAs, carbohydrates, phenols, polyphenols, pigments, toxins, pesticides, vitamins, additives, small organic and inorganic ions and other compounds found in foods and beverages are reviewed, as well as those applications of CE for monitoring food interactions and food processing. The use of microchips, CE‐MS and chiral‐CE in food analysis is also discussed as well as other current and foreseen trends in this area of research including new developments in F... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5482746 Wed, 07 Dec 2011 05:00:00 +0100 5482746 Recent developments and applications of EMMA in enzymatic and derivatization reactions http://www.medworm.com/index.php?rid=5482745&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100366 AbstractThis review provides systematic coverage of examples in the field of in‐capillary electrophorecially mediated microanalysis (EMMA). The recent developments and applications in the time period up to mid 2011 have been described, as well as relevant older papers. The basic principles and modes of in‐capillary assays have been demonstrated. An overview is also given of the various injection, separation and detection modes implemented in combination with EMMA. The review is presented in two parts mainly dealing with (i) enzymatic and (ii) derivatization or chemical reactions. Finally, the future trends of CE in performing and monitoring reactions have been drawn. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5482745 Wed, 07 Dec 2011 05:00:00 +0100 5482745 Recent approaches in sensitive enantioseparations by CE http://www.medworm.com/index.php?rid=5482748&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100404 AbstractThe latest strategies and instrumental improvements for enhancing the detection sensitivity in chiral analysis by CE are reviewed in this work. Following the previous reviews by García‐Ruiz et al. (Electrophoresis 2006, 27, 195–212) and Sánchez‐Hernández et al. (Electrophoresis 2008, 29, 237–251; Electrophoresis 2010, 31, 28–43), this review includes those papers that were published during the period from June 2009 to May 2011. These works describe the use of offline and online sample treatment techniques, online sample preconcentration techniques based on electrophoretic principles, and alternative detection systems to UV–Vis to increase the detection sensitivity. The application of the above‐mentioned strategies, either alone or combined, to improve the sensitivi... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5482748 Tue, 06 Dec 2011 05:00:00 +0100 5482748 Growing trend of CE at the omics level: The frontier of systems biology – An update http://www.medworm.com/index.php?rid=5482751&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100344 AbstractOmics is the study of proteins, peptides, genes, and metabolites in living organisms. Systems biology aims to understand the system through the study of the relationship between elements such as genes and proteins in biological system. Recently, systems biology emerged as the result of the advanced development of high‐throughput analysis technologies such as DNA sequencers, DNA arrays, and mass spectrometry for omics studies. Among a number of analytical tools and technologies, CE and CE coupled to MS are promising and relatively rapidly developing tools with the potential to provide qualitative and quantitative analyses of biological molecules. With an emphasis on CE for systems biology, this review summarizes the method developments and applications of CE for the genomic, trans... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5482751 Mon, 05 Dec 2011 05:00:00 +0100 5482751 Recent developments in CE and CEC of peptides (2009–2011) http://www.medworm.com/index.php?rid=5482750&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100419 AbstractThe review brings a comprehensive survey of the recent developments of high‐performance electroseparation methods in capillary and microchip formats: zone electrophoresis, isotachophoresis, isoelectric focusing, affinity electrophoresis, electrokinetic chromatography and electrochromatography. Applications of these techniques to analysis, isolation, purification and physicochemical and biochemical characterization of peptides are described. Advances in the investigation of electromigration properties of peptides, and in the methodology of their analysis, such as sample preparation, adsorption suppression, EOF control and detection, are presented. New developments, in particular, CE and CEC modes are reported and several types of their applications to peptide analysis are describe... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5482750 Mon, 05 Dec 2011 05:00:00 +0100 5482750 CE and CEC analysis of phytochemicals in herbal medicines http://www.medworm.com/index.php?rid=5482749&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100347 AbstractCE and CEC, due to their versatility and high efficiency, have attracted great interest in the analysis of phytochemicals in herbs and their preparations. Previously, we reviewed the analysis of phytochemical bioactive compounds by CE in 2006 (Electrophoresis 2006, 27, 4808–4819) or CEC in 2010 (Electrophoresis 2010, 31, 260–277). This review followed the previous studies and covered the literature published since 2006 for CE and 2009 for CEC (excluding those mentioned in the two previous reviews), which emphasized the development of CE and CEC techniques in phytochemical analysis. In addition, sample preparation and detection were also discussed. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5482749 Mon, 05 Dec 2011 05:00:00 +0100 5482749 Role of streaming potential on pulsating mass flow rate control in combined electroosmotic and pressure‐driven microfluidic devices http://www.medworm.com/index.php?rid=5542091&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100414 AbstractIn the present study, we investigate the implications of streaming potential on the mass flow rate control in a microfluidic device actuated by the combined application of a pulsating pressure gradient and a pulsating, externally applied, electric field. We demonstrate that the temporal dynamics due to streaming potential effects may lead to interesting non‐trivial aspects of the resultant transport characteristics. Our results highlight the importance of an adequate accounting of the streaming potential effects for temporally tunable mass flow rate control strategies, which may act as a useful design artifice to augment mass flow rates in practical scenarios. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5542091 Thu, 01 Dec 2011 05:00:00 +0100 5542091 Meetings Diary http://www.medworm.com/index.php?rid=5512043&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190121 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512043 Thu, 01 Dec 2011 05:00:00 +0100 5512043 Call for Papers http://www.medworm.com/index.php?rid=5512042&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190119 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512042 Thu, 01 Dec 2011 05:00:00 +0100 5512042 Plasma proteomics for biomarker discovery: A study in blue http://www.medworm.com/index.php?rid=5512041&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100307 AbstractThe performance of Cibacron Blue dye (HiTrapBlue or Affigel Blue) in depleting albumin from plasma, as a pre‐treatment for biomarker searching in the low‐abundance proteome, is here assessed. It is shown that (i) co‐depletion of non‐albumin species is an ever‐present hazard; (ii) the only proper eluant able to release quantitatively the proteins bound to the dye is boiling 4% SDS‐25 mM DTT, an ion shock (2 M NaCl) being quite ineffective in releasing the low‐abundance species tightly bound to the dye moiety; (iii) the mechanism of dye–protein interaction, after an initial ion–ion docking, is a robust hydrophobic interaction, which progressively augments at lower and lower pH values; (iv) at pH 2.2 in the presence of 0.1% TFA, the blue resin behaves, for all pr... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512041 Thu, 01 Dec 2011 05:00:00 +0100 5512041 Changes in amniotic fluid and umbilical cord serum proteomic profiles of foetuses with intrauterine growth retardation http://www.medworm.com/index.php?rid=5512040&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100256 AbstractFoetal growth is a result of a complex net of processes, requiring coordination within the maternal, placental, and foetal compartments, the imbalance or lack of which may lead to intrauterine growth restriction (IUGR). IUGR is the major cause of perinatal morbidity and mortality, and is also related to enhanced morbidity and metabolic abnormalities later in life. In the present study, the protein profiles of umbilical cord serum (UCS) and amniotic fluid (AF) of ten IUGR and ten appropriate for gestational age newborns have been analysed by 2‐DE, and nanoHPLC‐Chip/MS technology. A total of 18 and 13 spots were found to be differentially expressed (p<0.01) in UCS and AF respectively. The unique differentially expressed proteins identified by MS/MS analysis were 14 in UCS, and... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512040 Thu, 01 Dec 2011 05:00:00 +0100 5512040 Proteome and phosphoproteome of primary cultured pig urothelial cells http://www.medworm.com/index.php?rid=5512039&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100220 AbstractEpithelial tissue lining the inner side of the urinary bladder is the most common target for bladder cancer‐related diseases. Bladders of freshly slaughtered pigs were utilised for a comprehensive analysis of the proteome and phosphoproteome of bladder epithelial cells. Following protein separation by 2‐D gel electrophoresis and identification by matrix‐assisted laser desorption/ionisation time‐of‐flight mass spectrometry (MALDI‐TOF‐MS) the first proteome and phosphoproteome maps of pig urinary bladder epithelial cells (PUBEC) were established. A total of 120 selected protein spots were identified. By using the La3+ enrichment method further developed in our laboratory we identified 31 phosphoproteins with minimal contamination by non‐phosphopeptides. The 2‐DE map... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512039 Thu, 01 Dec 2011 05:00:00 +0100 5512039 Native Red Electrophoresis – A new method suitable for separation of native proteins http://www.medworm.com/index.php?rid=5512038&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100310 AbstractA new type of native electrophoresis was developed to separate and characterize proteins. In this modification of the native blue electrophoresis, the dye Ponceau Red S is used instead of Coomassie Brilliant Blue to impose uniform negative charge on proteins to enable their electrophoretic separation according to their relative molecular masses. As Ponceau Red S binds less tightly to proteins, in comparison with Coomassie Blue, it can be easily removed after the electrophoretic separation and a further investigation of protein properties is made possible (e.g. an enzyme detection or electroblotting). The tested proteins also kept their native properties (enzyme activity or aggregation state). (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512038 Thu, 01 Dec 2011 05:00:00 +0100 5512038 High‐throughput lectin magnetic bead array‐coupled tandem mass spectrometry for glycoprotein biomarker discovery http://www.medworm.com/index.php?rid=5512037&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100341 AbstractAlterations in protein glycosylation occur during development and progression of many diseases, hence glycomics and glycoproteomics have emerged as important tools in glycobiomarker discovery. High‐throughput glycan profiling can now be achieved with the recent developments in MS‐based techniques. To enable identification and rapid monitoring of glycosylation changes in serum proteins, we developed a semi‐automated high‐throughput glycoprotein biomarker discovery platform termed lectin magnetic bead array‐coupled tandem mass spectrometry (LeMBA‐MS) which includes (i) effective single‐step serum glycoprotein isolation using a panel of 20 individual lectin‐coated magnetic beads in microplate format, (ii) on‐bead trypsin digestion, and (iii) nanoLC‐MS/MS with lecti... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512037 Thu, 01 Dec 2011 05:00:00 +0100 5512037 Evaluation of non‐reductive β‐elimination/Michael addition for glycosylation site determination in mucin‐like O‐glycopeptides http://www.medworm.com/index.php?rid=5512036&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100393 AbstractInvestigation of site‐specific protein O‐glycosylation remains a formidable task in post‐translational modification‐centred proteomics. In particular, the determination of O‐glycosylated amino acids in mucin‐like glycopeptides lags far behind the techniques for phosphorylation site and N‐glycosylation site identification, for which well‐established enrichment techniques are available. The present work investigated β‐elimination of mucin‐like O‐glycopeptides with a mild alkylamine base and concomitant Michael‐type addition using 2‐mercaptoethanol as nucleophile applied to synthetic GalNAcylated O‐glycopeptides as well as exoglycosidase‐treated endogenous peptides isolated from human blood plasma. This strategy permits O‐glycosylated sites to be unamb... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512036 Thu, 01 Dec 2011 05:00:00 +0100 5512036 Site‐specific characterisation of densely O‐glycosylated mucin‐type peptides using electron transfer dissociation ESI‐MS/MS http://www.medworm.com/index.php?rid=5512035&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100294 This study demonstrates the capabilities of ETD MS/MS for site‐specific characterisation of mucin‐type glycopeptides containing high‐density O‐linked glycan clusters, using accessible and relative low‐resolution/low‐mass accuracy IT MS instrumentation. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512035 Thu, 01 Dec 2011 05:00:00 +0100 5512035 Profiling of Endo H‐released serum N‐glycans using CE‐LIF and MALDI‐TOF‐MS – Application to rheumatoid arthritis http://www.medworm.com/index.php?rid=5512034&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100250 We report here the characterization of high‐mannose and hybrid‐type N‐glycans in total human serum. To this end, N‐glycans were released using Endo‐β‐N‐acetylglucosaminidase H (Endo H) and analyzed by CE‐LIF and MALDI‐TOF‐MS. We found that the high‐mannose structures Man5–9GlcNAc1 represented the majority of the pool. The monoglucosylated structure Glc1Man9GlcNAc1 as well as four hybrid structures could be identified. Then, we compared the Endo H‐released serum glycome of patients suffering from rheumatoid arthritis with healthy controls as mannose‐binding lectin deficiency (MBL) and modulation of α‐mannosidase activity were previously associated with this disease. Interestingly, we observed that both high‐mannose and hybrid structures were fairly constant... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512034 Thu, 01 Dec 2011 05:00:00 +0100 5512034 Highly sensitive capillary electrophoresis analysis of N‐linked oligosaccharides in glycoproteins following fluorescence derivatization with rhodamine 110 and laser‐induced fluorescence detection http://www.medworm.com/index.php?rid=5512033&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100258 We describe a highly sensitive CE with laser‐induced fluorescence (LIF) detection for the analysis of N‐linked oligosaccharides in glycoproteins using rhodamine 110 as a fluorescence derivatization reagent. One CE separation is performed using a fused‐silica capillary and neutral pH buffer conditions and allows for the separation of sialo‐oligosaccharides according to the number of sialic acids. An alternate separation is performed using the same capillary and acidic pH buffer conditions, enabling the separation of asialo‐oligosaccharides according to their sizes. The derivatization and separation conditions for the analysis of sialo‐ and asialo‐oligosaccharides were optimized. Furthermore, we applied the proposed method for the analyses of N‐linked sialo‐ and asialo‐ol... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512033 Thu, 01 Dec 2011 05:00:00 +0100 5512033 Analysis of glycans derived from glycoconjugates by capillary electrophoresis‐mass spectrometry http://www.medworm.com/index.php?rid=5512032&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100342 AbstractThe high structural variation of glycan derived from glycoconjugates, which substantially increases with the molecular size of a protein, contributes to the complexity of glycosylation patterns commonly associated with glycoconjugates. In the case of glycoproteins, such variation originates from the multiple glycosylation sites of proteins and the number of glycan structures associated with each site (microheterogeneity). The ability to comprehensively characterize highly complex mixture of glycans has been analytically stimulating and challenging. Although the most powerful MS and MS/MS techniques are capable of providing a wealth of structural information, they are still not able to readily identify isomeric glycan structures without high‐order MS/MS (MSn). The analysis of isom... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512032 Thu, 01 Dec 2011 05:00:00 +0100 5512032 Recent advances in hydrophilic interaction liquid chromatography (HILIC) for structural glycomics http://www.medworm.com/index.php?rid=5512031&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100247 AbstractThis review presents recent progress in employing hydrophilic interaction liquid chromatography (HILIC) for glycan and glycopeptides analysis. After an introduction of this technique, the following themes are addressed: (i) implementation of HILIC in large‐scale studies for analyzing the human plasma N‐glycome; (ii) the use of HILIC UPLC (ultrahigh pressure liquid chromatography) for fast high‐resolution runs and its successful application with online MS for glycan and glycopeptide analysis; (iii) high‐throughput profiling using HILIC solid‐phase extraction in combination with MS detection; (iv) HILIC sample preparation for CE and CGE; (v) the latest glycoproteomic approaches implementing HILIC separation; (vi) future perspectives of HILIC including its use in large‐sca... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512031 Thu, 01 Dec 2011 05:00:00 +0100 5512031 Glycomics and glycoproteomics http://www.medworm.com/index.php?rid=5512030&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190117 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512030 Thu, 01 Dec 2011 05:00:00 +0100 5512030 Contents – Electrophoresis 24'2011 http://www.medworm.com/index.php?rid=5512029&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190122 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512029 Thu, 01 Dec 2011 05:00:00 +0100 5512029 Editorial Board: Electrophoresis 24'2011 http://www.medworm.com/index.php?rid=5512028&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190120 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512028 Thu, 01 Dec 2011 05:00:00 +0100 5512028 Cover Picture: Electrophoresis 24'2011 http://www.medworm.com/index.php?rid=5512027&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190118 AbstractIssue no. 24 is in one major part a Focus Issue on Glycomics and Glycoproteomics that includes 12 contributions “describing the development of new analytical methods or improvement of existing methods, permitting enhanced and sensitive analysis of glycans and glycoproteins.” The first part of the Focus Issue “includes two review articles critically evaluating the current status of glycan analysis by both hydrophilic interaction liquid chromatography and capillary electrophoresis‐mass spectrometry.” The second part of this Focus Issue “includes 4 research articles describing improved methods for the analysis of glycans by capillary electrophoresis with laser‐induced fluorescence detection.” The third part “includes 4 research articles describing new mass spectromet... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512027 Thu, 01 Dec 2011 05:00:00 +0100 5512027 The challenge to quantify proteins with charge trains due to isoforms or conformers http://www.medworm.com/index.php?rid=5512024&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100321 AbstractSingle proteins separated by 2‐DE often show multiple spots spreading along the first dimension. In many cases, such charge trains are explained by isoform differences or by putative post‐translational modifications including phosphorylation, glycosylation and others. We now report that individual spots of such charge trains on 2‐D gels in fact often represent the same protein, but, apparently due to conformational changes, segregate to different isoelectric points. If MS analysis reveals protein identity, we therefore suggest integrating all individual spots within a charge train for quantification. Especially in quality control of pharmaceutical proteins, the integration of the spot groups of all active contents is preferable in order to obtain reproducible and reasonable q... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5512024 Thu, 01 Dec 2011 05:00:00 +0100 5512024 A novel open‐tubular capillary electrochromatography with magnetic nanoparticle coating as stationary phase http://www.medworm.com/index.php?rid=5500900&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100337 AbstractA novel open‐tubular capillary electrochromatography (OT‐CEC) with modified core/shell magnetic nanoparticles coating as stationary phase was introduced using external magnetic force to fix magnetic nanoparticles. The magnetic nanoparticles coating inside the capillary columns could be easily regenerated by removing and re‐applying the external magnetic field. Magnetic field intensity, concentration and flow rate of nanoparticles suspension were investigated to achieve simple and stable preparation. Mixture of five organic acids was used as the marker sample to evaluate the OT‐CEC system, and the relative column efficiency of anthranilic acid reaches 220 000 plates/m. The excellent within‐column and between‐column repeatability has been testified with the RSDs of rete... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5500900 Thu, 01 Dec 2011 05:00:00 +0100 5500900 Capillary electrophoresis of natural products: Highlights of the last five years (2006–2010) http://www.medworm.com/index.php?rid=5482744&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100223 AbstractAn extensive search of the published research and review articles indicated a growing number of works that employed electroseparation techniques. Capillary zone electrophoresis (CZE) and electrokinetic chromatography (EKC), in particular, were found to be popular for the analyses of natural products. This review outlines the important developments in this field over the years, especially during the 2006–2010 period. An overview of the natural product applications such as pharmaceuticals/herbal products, fingerprinting and quality control, food and food contaminants, and toxicological compounds of interest to forensics were presented. Important areas of detection strategies, microchips, sample preconcentration, and chiral separations were also discussed. Hence, quick information w... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5482744 Thu, 01 Dec 2011 05:00:00 +0100 5482744 Meetings Diary http://www.medworm.com/index.php?rid=5464898&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190115 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464898 Thu, 01 Dec 2011 05:00:00 +0100 5464898 Call for Papers http://www.medworm.com/index.php?rid=5464897&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190113 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464897 Thu, 01 Dec 2011 05:00:00 +0100 5464897 Microfluidic chip‐capillary electrophoresis with dynamic multi‐segment standard addition for rapidly identifying nephrolithiasis markers in urine http://www.medworm.com/index.php?rid=5464896&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100213 AbstractA microchip‐CE device was fabricated for bed‐side monitoring of nephrolithiasis biomarkers in urine by incorporating on‐chip continuous passive mixing and standard addition to reduce sample matrix interference, increase sample throughput and eliminate accessories for active mixing. Under optimized conditions with buffer containing 20 mM borate and 0.5 mM CTAB at pH 10.3, sample and standards injected electrokinetically at −350 V for 10 s for online mixing in a Y‐merging flow microchannel prior to CE separation and UV detection at 210 nm, both inhibitors (citrate, CA) and promoters (oxalate, OA and uric acid, UA) for nephrolithiasis can be separated and determined in human urine in a single run completed within 10 min after a simple 50‐fold sample dilution an... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464896 Thu, 01 Dec 2011 05:00:00 +0100 5464896 Rapid detection of dysfunctional high‐density lipoproteins using isoelectric focusing‐based microfluidic device to diagnose senescence‐related disease http://www.medworm.com/index.php?rid=5464895&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100361 In conclusion, gA‐I‐rHDL and E‐HDL share several electrophoretic properties with multimerization and faster mobility in microfluidic channels, depending on the isoelectric point. These results can be applied to develop a rapid detection system for modified HDL to predict the extent of aging and aging‐related metabolic diseases, such as cardiovascular disease and diabetes. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464895 Thu, 01 Dec 2011 05:00:00 +0100 5464895 2‐D t‐ITP/CZE determination of clinical urinary proteins using a microfluidic‐chip capillary electrophoresis device http://www.medworm.com/index.php?rid=5464894&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100214 AbstractTo replace the time‐consuming sample pretreatment procedure, a microfluidic chip‐CE device incorporating on‐chip sample desalting/preconcentration with transient isotachophoresis (ITP)/capillary zone electrophoresis (CZE) was fabricated to perform sequential on‐chip sample pretreatment and CE determination of four urinary proteins in clinical samples. On‐chip sample desalting, clean‐up and analyte preconcentration enable removing interfering sample matrix prior to transferring analytes to separation capillary for transient ITP/CZE determination. Four important urinary proteins transferrin, β2‐microglobulin, human serum albumin (HSA) and immunoglobulin G (IgG), investigated were shown to achieve quantitation limits sufficiently high to meet medical requirements, sensi... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464894 Thu, 01 Dec 2011 05:00:00 +0100 5464894 Polyelectrolytes in multivalent salt solutions http://www.medworm.com/index.php?rid=5464893&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100319 AbstractWe study conformational and electrophoretic properties of polyelectrolytes (PEs) in tetravalent salt solutions under the action of electric fields by means of molecular dynamics simulations. Chain conformations are found to have a sensitive dependence on the salt concentration Cs. As Cs is increased, the chains first shrink to a globular structure and subsequently re‐expand above a critical concentration Cs*. An external electric field can further alter the chain conformation. If the field strength E is larger than a critical value E*, the chains are elongated. E* is shown to be a function of Cs by using two estimators EI* and EII* through the study of the polarization energy and the onset point of chain unfolding, respectively. The electrophoretic mobility of the chains depends ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464893 Thu, 01 Dec 2011 05:00:00 +0100 5464893 PDMS microchip coated with polydopamine/gold nanoparticles hybrid for efficient electrophoresis separation of amino acids http://www.medworm.com/index.php?rid=5464892&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100403 AbstractIn this paper, a novel, simple, economical and environmentally friendly method based on in situ chemically induced synthesis strategy was designed and developed for the modification of a poly(dimethylsiloxane) (PDMS) microchip channel with polydopamine/gold nanoparticles (PDA/Au NPs) to create a hydrophilic and biofouling resistant surface. Dopamine as a reductant and a monomer, and HAuCl4 as an oxidant to trigger dopamine polymerization and the source of metallic nanoparticles, were filled into the PDMS microchannel to yield in situ a well‐distributed and robust PDA/Au NP coating. Au NPs were highly and uniformly dispersed in/on the PDA matrix with a narrow size distribution, as verified by scanning electron microscopy and UV‐vis spectra. Compared with the native PDMS microcha... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464892 Thu, 01 Dec 2011 05:00:00 +0100 5464892 Recent advances in single‐molecule detection on micro‐ and nano‐fluidic devices http://www.medworm.com/index.php?rid=5464891&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100159 AbstractSingle‐molecule detection (SMD) allows static and dynamic heterogeneities from seemingly equal molecules to be revealed in the studies of molecular structures and intra‐ and inter‐molecular interactions. Micro‐ and nanometer‐sized structures, including channels, chambers, droplets, etc., in microfluidic and nanofluidic devices allow diffusion‐controlled reactions to be accelerated and provide high signal‐to‐noise ratio for optical signals. These two active research frontiers have been combined to provide unprecedented capabilities for chemical and biological studies. This review summarizes the advances of SMD performed on microfluidic and nanofluidic devices published in the past five years. The latest developments on optical SMD methods, microfluidic SMD platforms,... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464891 Thu, 01 Dec 2011 05:00:00 +0100 5464891 Micro‐ and Nanofluidics in Asia Pacific http://www.medworm.com/index.php?rid=5464890&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190111 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464890 Thu, 01 Dec 2011 05:00:00 +0100 5464890 Contents – Electrophoresis 23'2011 http://www.medworm.com/index.php?rid=5464889&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190116 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464889 Thu, 01 Dec 2011 05:00:00 +0100 5464889 Editorial Board: Electrophoresis 23'2011 http://www.medworm.com/index.php?rid=5464888&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190114 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464888 Thu, 01 Dec 2011 05:00:00 +0100 5464888 Cover Picture: Electrophoresis 23'2011 http://www.medworm.com/index.php?rid=5464887&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190112 AbstractIssue no. 23 is a special issue on Micro‐ and Nanofluidics in Asia Pacific. It has 18 contributions including review, basic technology, and applications in DNA, protein and cells of the multidisciplinary nature of the micro‐ and nanofluidics science. By dedicating this edition to micro‐ and nanofluidics in Asia Pacific, it is hoped “that it reflects the most recent developments in the Lab‐on‐Chip community in this most populous and economically vibrant part of the world.” Read this issue to keep in touch with “the developments and advances in the microfluidic community of this region”.Featured articles include:Recent advances in single‐molecule detection on micro‐ and nano‐fluidic devices ((10.1002/elps.201100159))Rapid microparticle patterning by enhanced ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464887 Thu, 01 Dec 2011 05:00:00 +0100 5464887 Surface modification for PDMS‐based microfluidic devices http://www.medworm.com/index.php?rid=5464883&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100482 AbstractThis review focuses on advances reported from April 2009 to May 2011 in PDMS surface modifications for the application in microfluidic devices. PDMS surface modification techniques presented here include improved plasma and graft polymer coating, dynamic surfactant treatment, hydrosilylation‐based surface modification and surface modification with nanomaterials such as carbon nanotubes and metal nanoparticles. Recent efforts to generate topographical and chemical patterns on PDMS are also discussed. The described surface modifications not only increase PDMS wettability, inhibit or reduce non‐specific adsorption of hydrophobic species onto the surfaces in the act, but also result in the display of desired functional groups useful for molecular separations, biomolecular detection... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464883 Thu, 01 Dec 2011 05:00:00 +0100 5464883 CE of inorganic species – A review of methodological advancements over 2009–2010 http://www.medworm.com/index.php?rid=5464886&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100357 This article is the seventh in a series examining biannually the methodological developments in the field of CE analysis of inorganic species and covers relevant documents published between January 2009 and December 2010. Following an analysis of the significant accomplishments that have impacted the field in two recent years, a survey of advances in general CE methodology is presented. Subsequently, several notable trends that can be perceived in this well‐established field are discussed: the continuing rise of ME and consequent development of suitable detection techniques, most notably contactless conductivity detection, the constant pace of advances in speciation analysis, and an increase in non‐analytical CE applications to study complexation and (bio)transformation reactions of me... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464886 Wed, 30 Nov 2011 05:00:00 +0100 5464886 Recent novel MEKC applications to analyze free amino acids in different biomatrices: 2009–2010 http://www.medworm.com/index.php?rid=5464885&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100336 This report intends to provide an updated overview of the most important methodological developments of MEKC in the field of qualitative/quantitative analysis of free amino acids in different matrices. A good number of articles published in the years 2009–2010 addresses the main applications of such procedures together with their advantages and/or drawbacks. The usefulness of chiral CE selective methods for the separation of D‐amino acids in biological and food samples and the use of microchips, as well as other foreseen trends in different areas, are also discussed. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464885 Wed, 30 Nov 2011 05:00:00 +0100 5464885 Recent advances in the analysis of antibiotics by CE and CEC http://www.medworm.com/index.php?rid=5464884&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100409 This article reviews the recent developments achieved in the analysis of antibiotics by CE and CEC. CZE has mainly been employed although other separation modes have also been used. Different detection systems coupled to CE have been reported for antibiotic determination. Enhancement on sensitivity through the use of diverse offline, inline, and online preconcentration approaches is also described. Special attention has been paid to sample treatment steps and to the applications developed in different research areas such as the pharmaceutical, biological, food, and environmental. This manuscript covers the period of time from the previous review published in June 2009 until May 2011. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5464884 Wed, 30 Nov 2011 05:00:00 +0100 5464884 Liquid‐phase‐based separation systems for depletion, prefractionation and enrichment of proteins in biological fluids and matrices for in‐depth proteomics analysis – An update covering the period 2008–2011 http://www.medworm.com/index.php?rid=5453894&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100431 AbstractThis review article expands on the previous one (Jmeian, Y. and El Rassi, Z. Electrophoresis 2009, 30, 249–261) by reviewing pertinent literature in the period extending from early 2008 to the present. Similar to the previous review article, the present one is concerned with proteomic sample preparation (e.g. depletion of high‐abundance proteins, reduction of the protein dynamic concentration range, enrichment of a particular subproteome), and the subsequent chromatographic and/or electrophoretic prefractionation prior to peptide separation and identification by LC‐MS/MS. This review article differs from the first version published in Electrophoresis 2009, 30, 249–261 by expanding on capturing/enriching subglycoproteomics by lectin affinity chromatography. Ninety‐eight ar... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5453894 Mon, 28 Nov 2011 05:00:00 +0100 5453894 Recent advances in miniaturisation – The role of microchip electrophoresis in clinical analysis http://www.medworm.com/index.php?rid=5453893&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100454 AbstractThis review aims to highlight the current role of microchip CE (MCE) in clinical analysis to date, and also its future potential in this important area. One of the most notable advancements in separation science, which has accelerated in the last decade, has been the use of plastic and glass microchips to achieve high‐speed electrophoresis separations in seconds, requiring only pico or nanolitre sample volumes. So far, in the clinical laboratory, MCE has lent itself to the resolution of very complex challenging analytes such as DNA, RNA, protein analysis, cellular components and other disease biomarkers. At present, most basic clinical laboratories rely heavily upon various kinds of enzymatic immunoassays as these methods offer speed, specificity, reliability and are well establi... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5453893 Mon, 28 Nov 2011 05:00:00 +0100 5453893 Analysis of mucosal mucins separated by SDS‐urea agarose polyacrylamide composite gel electrophoresis http://www.medworm.com/index.php?rid=5447383&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100374 AbstractEfficient separation of mucins (200 kDa–2 MDa) was demonstrated using gradient SDS agarose/polyacrylamide composite gel electrophoresis (SDS‐AgPAGE). Inclusion of urea (SDS‐UAgPAGE) in the gels casting were shown to have no effect on the migration of mucins in the gel and allowed casting of gel at room temperature. This simplified the procedure for multiple casting of agarose polyacrylamide gradients and increased reproducibility of these gels. Hence, the implementation of urea makes the technique applicable for high throughput isolation and screening of mucin oligosaccharides by LC‐MS after releasing the oligosaccharides from isolated, blotted mucin subpopulations. It was also shown that the urea addition had no effect on other supporting applications such as western a... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5447383 Thu, 24 Nov 2011 05:00:00 +0100 5447383 The effect of miR‐7 on behavior and global protein expression in glioma cell lines http://www.medworm.com/index.php?rid=5447382&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100230 In conclusion, the absence of miR‐7 function could cause downstream molecules to switch on or off, resulting in glioma development, invasion, and metastases. MiR‐7‐based gene treatment may be a novel anti‐invasion therapeutic strategy for malignant glioma. (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5447382 Thu, 24 Nov 2011 05:00:00 +0100 5447382 Electron detachment dissociation of fluorescently labeled sialylated oligosaccharides http://www.medworm.com/index.php?rid=5447381&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100327 AbstractWe explored the application of electron detachment dissociation (EDD) and infrared multiphoton dissociation (IRMPD) tandem mass spectrometry to fluorescently labeled sialylated oligosaccharides. Standard sialylated oligosaccharides and a sialylated N‐linked glycan released from human transferrin were investigated. EDD yielded extensive glycosidic cleavages and cross‐ring cleavages in all cases studied, consistently providing complementary structural information compared with infrared multiphoton dissociation. Neutral losses and satellite ions such as C−2H ions were also observed following EDD. In addition, we examined the influence of different fluorescent labels. The acidic label 2‐aminobenzoic acid (2‐AA) enhanced signal abundance in negative‐ion mode. However, few cr... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5447381 Thu, 24 Nov 2011 05:00:00 +0100 5447381 Rapid determination of protein binding constant by a pressure‐mediated affinity capillary electrophoresis method http://www.medworm.com/index.php?rid=5437064&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100211 AbstractA new pressure‐mediated affinity capillary electrophoresis method for the rapid and accurate determination of drug–protein binding constants is described. A special combination of pressure and electrophoresis is used to shorten the electrophoresis and the overall analysis time to only a few minutes. At the same time, the suitability of this method is checked against a traditional fluorescence spectroscopy method. The binding constants of bovine serum albumin and a total of eight drugs with different pKa have been evaluated and compared with those determined by the fluorescence spectroscopy method and other methods in literature. The results indicate that the P‐ACE method is well suited for the determination of binding constants with weak interaction (Kb<105 M−1). (Sour... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5437064 Mon, 21 Nov 2011 05:00:00 +0100 5437064 Exploitation of detergent thermodynamics in the direct solubilization of myelin membrane proteins for two‐dimensional gel electrophoresis for proteomic analysis http://www.medworm.com/index.php?rid=5437063&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100248 AbstractPerforming 2‐DE of lipid‐rich multilamellar membranes like myelin is a cumbersome task. However, for understanding its molecular organization and changes during diseases, identification of proteins of myelin is essential. Although the 2‐D‐proteomic approach of myelin has been employed to understand the myelin proteome, representation of myelin proteins in its entirety is still a challenge. 2‐DE profiling of myelin proteins is very important for the detection of immuno‐reactivity to myelin proteins from various biological fluids following Western blotting in diseases like multiple sclerosis. Here we developed a novel approach by exploiting the thermodynamic principles behind detergent‐mediated solubilization of myelin membranes without any conventional processing of my... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5437063 Mon, 21 Nov 2011 05:00:00 +0100 5437063 Improved sample preparation for CE‐LIF analysis of plant N‐glycans http://www.medworm.com/index.php?rid=5437062&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100268 AbstractIn view of glycomics studies in plants, it is important to have sensitive tools that allow one to analyze and characterize the N‐glycans present on plant proteins in different species. Earlier methods combined plant‐based sample preparations with CE‐LIF N‐glycan analysis but suffered from background contaminations, often resulting in non‐reproducible results. This publication describes a reproducible and sensitive protocol for the preparation and analysis of plant N‐glycans, based on a combination of the ‘in‐gel release method’ and N‐glycan analysis on a multicapillary DNA sequencer. Our protocol makes it possible to analyze plant N‐glycans starting from low amounts of plant material with highly reproducible results. The developed protocol was validated for di... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5437062 Mon, 21 Nov 2011 05:00:00 +0100 5437062 Online enzymatic sequencing of glycans from Trastuzumab by phospholipid‐assisted capillary electrophoresis http://www.medworm.com/index.php?rid=5437061&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100432 AbstractCE separations of glycans taken from the cancer drug, Trastuzumab (Herceptin®), were accomplished using phospholipid additives. Glycans were labeled with 1‐aminopyrene‐3,6,8‐trisulfonic acid and were separated with efficiencies as high as 510 000 theoretical plates in a 60.2 cm 25 μm id fused‐silica capillary. The thermally tunable phospholipid was loaded into the capillary when it possessed a viscosity similar to that of water. The temperature was increased, and the separations were performed when the material exhibited higher viscosity. Enzymes were integrated into the separation with the phospholipid additive. Neuraminidase, β1‐4 galactosidase, and β‐N‐acetylglucosaminidase were injected into the capillary without covalent modification and used for enzyme... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5437061 Mon, 21 Nov 2011 05:00:00 +0100 5437061 A simple elastic membrane‐based microfluidic chip for the proliferation and differentiation of mesenchymal stem cells under tensile stress http://www.medworm.com/index.php?rid=5396422&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100237 AbstractThis work presents a simple membrane‐based microfluidic chip for the investigation of proliferation and differentiation of mesenchymal stem cells (MSCs) under mechanical stimuli. The cyclic tensile stress was generated by the deformation of elastic PDMS membrane sandwiched between the two layer microfluidic chip via actuated negative pressure, and the cultured MSCs on membrane were subjected to different orders of tensile stress. The results suggest that mechanical stimuli are attributed to the different phenomena of MSCs in cell proliferation and differentiation. The higher tensile stress (>3.5) promoted obvious proliferation, osteogenesis and reduced adipogenesis in MSCs, indicating the possible regulative role of tensile stress in modifying the osteogenesis/adipogenesis bal... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5396422 Thu, 10 Nov 2011 05:00:00 +0100 5396422 Development of a double‐layer microfluidic chip with flow medium for chemotherapy resistance analysis of lung cancer http://www.medworm.com/index.php?rid=5396421&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100086 This study aimed at establishing a double‐layer chip to integrate the operations including the cell culture, the identification of the protein and the detection of the cell viability onto a platform systematically and supplied with flow fresh medium continuously via a syringe pump to mimic the microenvironment in vivo. With this device, human non‐small cell lung cancer cell line (SPCA‐1) was cultured well; the expression and the activity of multidrug resistance‐associated protein (MRP1) were detected by immunofluorescence assay for the cells pretreated with or without MK‐571, a known inhibitor of MRP1; apoptosis percentages were assayed for the cells after being treated by the anticancer drug etoposide (VP‐16). The results demonstrated that the function of the MRP1 was inhibite... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5396421 Thu, 10 Nov 2011 05:00:00 +0100 5396421 Sequential microfluidic droplet processing for rapid DNA extraction http://www.medworm.com/index.php?rid=5396420&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100078 AbstractThis work describes a novel droplet‐based microfluidic device, which enables sequential droplet processing for rapid DNA extraction. The microdevice consists of a droplet generation unit, two reagent addition units and three droplet splitting units. The loading/washing/elution steps required for DNA extraction were carried out by sequential microfluidic droplet processing. The movement of superparamagnetic beads, which were used as extraction supports, was controlled with magnetic field. The microdevice could generate about 100 droplets per min, and it took about 1 min for each droplet to perform the whole extraction process. The extraction efficiency was measured to be 46% for λ‐DNA, and the extracted DNA could be used in subsequent genetic analysis such as PCR, demonstrati... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5396420 Thu, 10 Nov 2011 05:00:00 +0100 5396420 Solvent bonding of poly(methyl methacrylate) microfluidic chip using phase‐changing agar hydrogel as a sacrificial layer http://www.medworm.com/index.php?rid=5396419&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100436 In this report, a solvent bonding method based on phase‐changing agar hydrogel has been developed for the fabrication of poly(methyl methacrylate) (PMMA) microfluidic chips. Prior to bonding, the channels and the reservoir ports on PMMA channel plates were filled with molten agar hydrogel that could gelate to form solid sacrificial layers at room temperature. Subsequently, PMMA cover sheets were covered on the channeled plates and 1,2‐dichlororethane was applied to the interspaces between them. The agar hydrogel in the channels could prevent the bonding solvent and the softened surface of the PMMA cover sheets from filling in the channels. After solvent bonding, the agar hydrogel in the channels and the reservoir ports was melted and removed under pressure. The sealed channels in the c... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5396419 Thu, 10 Nov 2011 05:00:00 +0100 5396419 A prototypic system of parallel electrophoresis in multiple capillaries coupled with microwell arrays http://www.medworm.com/index.php?rid=5396418&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100339 We present a microfluidic system that can be directly coupled with microwell array and perform parallel electrophoresis in multiple capillaries simultaneously. The system is based on an array of glass capillaries, fixed in a polydimethylsiloxane (PDMS) microfluidic scaffold, with one end open for interfacing with microwells. In this capillary array, every two adjacent capillaries act as a pair to be coupled with one microwell; samples in the microwells are introduced and separated by simply applying voltage between two electrodes that are placed at the other ends of capillaries; thus no complicated circuit design is required. We evaluate the performance of this system and perform multiple CE with direct sample introduction from microwell array. Also with this system, we demonstrate the ana... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5396418 Thu, 10 Nov 2011 05:00:00 +0100 5396418 A SERS‐active microfluidic device with tunable surface plasmon resonances http://www.medworm.com/index.php?rid=5396417&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100309 AbstractA surface‐enhanced Raman scattering (SERS)‐active microfluidic device with tunable surface plasmon resonances is presented here. It is constructed by silver grating substrates prepared by two‐beam laser interference of photoresists and subsequent metal evaporation coating, as well as PDMS microchannel derived from soft lithography. By varying the period of gratings from 200 to 550 nm, surface plasmon resonances (SPRs) from the metal gratings could be tuned in a certain range. When the SPRs match with the Raman excitation line, the highest enhancement factor of 2×107 is achieved in the SERS detection. The SERS‐active microchannel with tunable SPRs exhibits both high enhancement factor and reproducibility of SERS signals, and thus holds great promise for applications of on... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5396417 Thu, 10 Nov 2011 05:00:00 +0100 5396417 Unsteady electroosmosis in a microchannel with Poisson–Boltzmann charge distribution http://www.medworm.com/index.php?rid=5396416&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100181 AbstractThe present study is concerned with unsteady electroosmotic flow (EOF) in a microchannel with the electric charge distribution described by the Poisson–Boltzmann (PB) equation. The nonlinear PB equation is solved by a systematic perturbation with respect to the parameter λ which measures the strength of the wall zeta potential relative to the thermal potential. In the small λ limits (λ≪1), we recover the linearized PB equation – the Debye–Hückel approximation. The solutions obtained by using only three terms in the perturbation series are shown to be accurate with errors <1% for λ up to 2. The accurate solution to the PB equation is then used to solve the electrokinetic fluid transport equation for two types of unsteady flow: transient flow driven by a suddenly appl... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5396416 Thu, 10 Nov 2011 05:00:00 +0100 5396416 Rapid microparticle patterning by enhanced dielectrophoresis effect on a double‐layer electrode substrate http://www.medworm.com/index.php?rid=5396425&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100232 We present a feasible dielectrophoresis (DEP) approach for rapid patterning of microparticles on a reusable double‐layer electrode substrate in microfluidics. Simulation analysis demonstrated that the DEP force was dramatically enhanced by the induced electric field on top interdigitated electrodes. By adjusting electric field intensity through the bottom electrodes on thin glass substrate (100 μm), polystyrene particles (10 μm) were effectively patterned by top electrodes within several seconds (<5 s). The particle average velocity can reach a maximum value of about 20.0±3.0 μm/s at 1 MHz with the strongest DEP force of 1.68 pN. This approach implements integration of functional electrodes into one substrate and avoids direct electrical connection to biological object... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5396425 Mon, 07 Nov 2011 05:00:00 +0100 5396425 Interconnected ordered nanoporous networks of colloidal crystals integrated on a microfluidic chip for highly efficient protein concentration http://www.medworm.com/index.php?rid=5396424&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100303 We report a controllable method to fabricate silica colloidal crystals at defined position in microchannel of microuidic devices using simple surface modification. The formed PCs (photonic crystals) in microfluidic channels were stabilized by chemical cross‐linking of Si‐O‐Si bond between neighboring silica beads. The voids among colloids in PCs integrated on microfluidic devices form interconnected nanoporous networks, which show special electroosmotic properties. Due to the “surface‐charge induced ion depletion effect” mechanism, FITC‐labeled proteins can be efficiently and selectively concentrated in the anodic boundary of the ion depletion zone. Using this device, about 103‐ to 105‐fold protein concentration was achieved within 10 min. The present simple on chip pro... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5396424 Mon, 07 Nov 2011 05:00:00 +0100 5396424 A comparative study of interfaces for microchip micellar electrokinetic chromatography‐electrospray ionization mass spectrometry using the surfactant ammonium dodecyl sulfate http://www.medworm.com/index.php?rid=5396423&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100288 AbstractUsing ammonium dodecyl sulfate (ADS) as the surfactant, the response of three common interfaces in the direct coupling of microchip micellar electrokinetic chromatography with electrospray ionization mass spectrometry was studied. In the range of 10–40 mM surfactant, a conventional sheath liquid interface provided poorer sensitivity than both sheathless interface and low‐sheath‐flow interface. At a surfactant concentration <20 mM, a low‐sheath‐flow interface exhibited less sensitivity than a sheathless interface; however, it outperformed the sheathless interface above a concentration of 20 mM. At a surfactant concentration above 20 mM, signal reduction due to dilution of the analyte compensated by signal enhancement gained from a reduction in ion suppression ef... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5396423 Mon, 07 Nov 2011 05:00:00 +0100 5396423 Developments in coupled solid‐phase extraction–capillary electrophoresis 2009–2011 http://www.medworm.com/index.php?rid=5453892&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100453 This article presents an overview of the design and application of coupled solid‐phase extraction‐capillary electrophoresis (SPE‐CE) systems that have been reported in the literature between January 2009 and July 2011. The present paper is an update of two previous review papers covering the years 2000–2009 (Electrophoresis 2008, 29, 108–128; Electrophoresis 2010, 31, 44–54). Both in‐line and on‐line SPE‐CE approaches are treated and outlined. Attention is paid to emerging technological developments, such as the use of carbon nanotubes and magnetic particles for on‐line extraction of sample components prior to CE analysis. Selected examples illustrate the applicability of SPE‐CE in biomedical, pharmaceutical, environmental and food analysis. A full overview of recent ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5453892 Tue, 01 Nov 2011 04:00:00 +0100 5453892 Enhanced sensitivity of LC‐MS analysis of permethylated N‐glycans through online purification http://www.medworm.com/index.php?rid=5447380&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100378 AbstractAberrant glycosylation of proteins and lipids has been implicated in many human diseases, thus prompting the need for reliable analytical methods that permit dependable quantification of glycans originating from biological specimens. MS of permethylated glycans is currently employed to monitor disease‐related aberrant glycosylation of proteins and lipids. However, enhancing the sensitivity of this type of analysis is still needed. Here, analysis of permethylated glycans at enhanced sensitivity is attained through miniaturized solid‐phase permethylation and online solid‐phase purification. Solid‐phase permethylation method was miniaturized by reducing the amount of sodium hydroxide beads (one‐third the original amount) packed in microspin columns. The efficiency of glycan ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5447380 Tue, 01 Nov 2011 04:00:00 +0100 5447380 Isolation of metallothionein from cells derived from aggressive form of high‐grade prostate carcinoma using paramagnetic antibody‐modified microbeads off‐line coupled with electrochemical and electrophoretic analysis http://www.medworm.com/index.php?rid=5437060&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100301 AbstractProstate cancer with altered zinc(II) cell metabolism is the second most frequently diagnosed cancer in developed countries. The alterations of zinc(II) metabolism can influence metabolism of other metal ions and can also be associated with the expression and translation of metal‐binding proteins including metallothioneins. The aim of this article was to optimize immunoseparation protocol based on paramagnetic beads conjugated with protein G for the isolation of metallothionein. Isolated metallothionein was determined by differential pulse voltammetry Brdicka reaction and SDS‐PAGE. Optimal conditions: antigen‐binding time – 60 min, temperature − 70°C, and buffer composition and pH – acetate buffer, pH 4.3, were determined. Under the optimized conditions, lysates from... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5437060 Tue, 01 Nov 2011 04:00:00 +0100 5437060 Erratum: A capillary electrophoretic system based on a novel microemulsion for the analysis of coenzyme Q10 in human plasma by electrokinetic chromatography http://www.medworm.com/index.php?rid=5427828&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190105 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427828 Tue, 01 Nov 2011 04:00:00 +0100 5427828 Meetings Diary http://www.medworm.com/index.php?rid=5427827&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190109 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427827 Tue, 01 Nov 2011 04:00:00 +0100 5427827 Call for Papers http://www.medworm.com/index.php?rid=5427826&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190107 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427826 Tue, 01 Nov 2011 04:00:00 +0100 5427826 Electrophoretic mobility measurements of fluorescent dyes using on‐chip capillary electrophoresis http://www.medworm.com/index.php?rid=5427825&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100210 We present an experimental study of the effect of pH, ionic strength, and concentrations of the electroosmotic flow (EOF)‐suppressing polymer polyvinylpyrrolidone (PVP) on the electrophoretic mobilities of commonly used fluorescent dyes (fluorescein, Rhodamine 6G, and Alexa Fluor 488). We performed on‐chip capillary zone electrophoresis experiments to directly quantify the effective electrophoretic mobility. We use Rhodamine B as a fluorescent neutral marker (to quantify EOF) and CCD detection. We also report relevant acid dissociation constants and analyte diffusivities based on our absolute estimate (as per Nernst–Einstein diffusion). We perform well‐controlled experiments in a pH range of 3–11 and ionic strengths ranging from 30 to 90 mM. We account for the influence of ioni... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427825 Tue, 01 Nov 2011 04:00:00 +0100 5427825 Numerical analysis of a rapid magnetic microfluidic mixer http://www.medworm.com/index.php?rid=5427824&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100254 This study is the first to analyze these pronounced finger patterns numerically, and the results are in good agreement with the experimental visualization of Wen et al. (Electrophoresis 2009, 30, 4179–4186).The large interfacial area that accompanies these fine finger structures and the dominant diffusion effects occurring around the circumferential regions of fingers significantly enhance the mixing performance. The mixing ratio can be as high as 95% within 2.0 s. at a distance of 3.0 mm from the mixing channel inlet when the applied peak magnetic field supplied by the DC power source exceeds 60 Oe. This study also presents a sample implementation of AC power actuation in a numerical simulation, an experimental benchmark, and a simulation of DC power actuation with the same peak m... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427824 Tue, 01 Nov 2011 04:00:00 +0100 5427824 Reassemblable quasi‐chip free‐flow electrophoresis with simple heating dispersion for rapid micropreparation of trypsin in crude porcine pancreatin http://www.medworm.com/index.php?rid=5427823&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100358 AbstractAn increasing number of small biosamples (e.g. proteins and enzymes) need micropreparation in lab. However, neither large‐scale free‐flow electrophoresis (LS‐FFE) nor chip FFE (C‐FFE) could fit the growing demands. Herein, a simple quasi‐chip FFE (QC‐FFE) was constructed. In contrast to C‐FFE, the features of QC‐FFE are as follows: (i) its separation chamber is reassemblable and rewashable avoiding discard of C‐FFE due to blockage of solute precipitation in chamber; (ii) its chamber size is 45 mm×30 mm×(80–500) μm (108–654 μL volume) having function of micropreparation; (iii) there are up to 16 outlets in QC‐FFE bestowing fine fraction for micropurification. The QC‐FFE was used for the micropurification of model enzyme of self‐digestible tryp... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427823 Tue, 01 Nov 2011 04:00:00 +0100 5427823 Rapid qualitative evaluation of DNA transcription factor NF‐κB by microchip electrophoretic mobility shift assay in mammalian cells http://www.medworm.com/index.php?rid=5427822&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100261 AbstractWe have developed a separation technique for DNA–protein complex based on electrophoretic mobility shift assay (EMSA) by microchip electrophoresis, which we call microchip electrophoretic mobility shift assay (μEMSA). To evaluate the μEMSA, we employed recombinant human nuclear factor‐κB (rhNF‐κB) and its consensus double‐stranded oligonucleotide (dsOligo) fluorescently labeled with Cy5. We carried out the electrophoretic separation of the consensus dsOligo‐rhNF‐κB complex and the unbound dsOligo in methylcellulose solution and confirmed rapid (∼200 s) and reliable identification and semi‐quantitation of the specific interaction between dsOligo and rhNF‐κB. The binding specificity of rhNF‐κB was confirmed by introducing non‐fluorescently labeled conse... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427822 Tue, 01 Nov 2011 04:00:00 +0100 5427822 Contactless dielectrophoretic spectroscopy: Examination of the dielectric properties of cells found in blood http://www.medworm.com/index.php?rid=5427821&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100351 AbstractThe use of non‐invasive methods to detect and enrich circulating tumor cells (CTCs) independent of their genotype is critical for early diagnostic and treatment purposes. The key to using CTCs as predictive clinical biomarkers is their separation and enrichment. This work presents the use of a contactless dielectrophoresis (cDEP) device to investigate the frequency response of cells and calculate their area‐specific membrane capacitance. This is the first demonstration of a cDEP device which is capable of operating between 10 and 100 kHz. Positive and negative dielectrophoretic responses were observed in red blood cells, macrophages, breast cancer, and leukemia cells. The area‐specific membrane capacitances of MDA‐MB231, THP‐1 and PC1 cells were determined to be 0.01518... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427821 Tue, 01 Nov 2011 04:00:00 +0100 5427821 Justification of rapid prototyping in the development cycle of thermoplastic‐based lab‐on‐a‐chip http://www.medworm.com/index.php?rid=5427820&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100249 AbstractDuring the developmental cycle of lab‐on‐a‐chip devices, various microstructuring techniques are required. While in the designing and assay implementation phase direct structuring or so‐called rapid‐prototyping methods such as milling or laser ablation are applied, replication methods like hot embossing or injection moulding are favourable for large quantity manufacturing. This work investigated the applicability of rapid‐prototyping techniques for thermoplastic chip development in general, and the reproducibility of performances in dependency of the structuring technique. A previously published chip for prenatal diagnosis that preconcentrates DNA via electrokinetic trapping and field‐amplified‐sample‐stacking and afterwards separates it in CGE was chosen as a mod... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427820 Tue, 01 Nov 2011 04:00:00 +0100 5427820 Label‐free analysis in chip electrophoresis applying deep UV fluorescence lifetime detection http://www.medworm.com/index.php?rid=5427819&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100204 AbstractHerein we introduce deep UV fluorescence lifetime detection in microfluidics applied for label‐free detection and identification of various aromatic analytes in chip electrophoresis. For this purpose, a frequency quadrupled Nd:YAG (neodymium‐doped yttrium aluminum garnet) picosecond laser at 266 nm was incorporated into an inverse fluorescence microscope setup with time‐correlated single photon counting detection. This allowed recording of photon timing with sub‐nanosecond precision. Thereby fluorescence decay curves are gathered on‐the‐fly and average lifetimes can be determined for each substance in the electropherogram. The aromatic compounds serotonin, propranolol, 3‐phenoxy‐1,2‐propanediol and tryptophan were electrophoretically separated using a fused‐si... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427819 Tue, 01 Nov 2011 04:00:00 +0100 5427819 Microfluidics and Miniaturization http://www.medworm.com/index.php?rid=5427818&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190104 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427818 Tue, 01 Nov 2011 04:00:00 +0100 5427818 Contents – Electrophoresis 22'2011 http://www.medworm.com/index.php?rid=5427817&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190110 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427817 Tue, 01 Nov 2011 04:00:00 +0100 5427817 Editorial Board: Electrophoresis 22'2011 http://www.medworm.com/index.php?rid=5427816&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190108 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427816 Tue, 01 Nov 2011 04:00:00 +0100 5427816 Cover Picture: Electrophoresis 22'2011 http://www.medworm.com/index.php?rid=5427815&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190106 AbstractIssue no. 22 is a special issue on Microfluidics and Miniaturization. It collects 26 original articles covering Fundamentals, New Technology and Applications of Microfluidic Systems. As microfabrication technology becomes more accessible to interdisciplinary research, it is interesting to see the directions of its practical use. With more than one third of the papers dealing with Cell Analyses, this issue points to one of the most important applications of microfluidic technology. This trend is also well documented by the two special issues focused on dielectrophoresis (issues nos. 17 and 18), which were published earlier this year”.Featured articles include:Label‐free analysis in chip electrophoresis applying deep UV fluorescence lifetime detection ((10.1002/elps.201100204))On... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5427815 Tue, 01 Nov 2011 04:00:00 +0100 5427815 Microfluidic synthesis of tunable poly‐(N‐isopropylacrylamide) microparticles via PEG adjustment http://www.medworm.com/index.php?rid=5404623&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100340 We present a microfluidic droplet method to synthesize a series of tunable poly(N‐isopropylacrylamide) (PNIPAM) microparticles by the addition of polyethylene glycols (PEGs). The PEGs are used as porogens and could be removed simply by washing step. By varying molecular weights and concentrations of the PEGs, morphologies and temperature‐sensitive properties of the formed PNIPAM microparticles are flexibly tuned. It is found that PEG of lower molecular weight induces smaller micropore sizes, and results in faster response rate. The volume changes prior to and after shrinkage can also be regulated by the addition of PEGs due to tuned homogeneities of micropores. The microparticles tuned by PEG1000 with ratio of added PEGs to NIPAM of 2:1 respond the fastest (120 s), whereas with ratio... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5404623 Tue, 01 Nov 2011 04:00:00 +0100 5404623 A simultaneous space sampling method for DNA fraction collection using a comb structure in microfluidic devices http://www.medworm.com/index.php?rid=5396415&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100362 AbstractFraction collection of selected components from a complex mixture plays a critical role in biomedical research, environmental analysis, and biotechnology. Here, we introduce a novel electrophoretic chip device based on a signal processing theorem that allows simultaneous space sampling for fractionation of ssDNA target fragments. Ten parallel extraction channels, which covered 1.5‐mm‐long sampling ranges, were used to facilitate the capturing of fast‐moving fragments. Furthermore, the space sampling extraction made it possible to acquire pure collection, even from partly overlapping fragments that had been insufficiently separated after a short electrophoretic run. Fragments of 180, 181, and 182 bases were simultaneously collected, and then the recovered DNA was PCR amplified... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5396415 Tue, 01 Nov 2011 04:00:00 +0100 5396415 Integration of microchip electrophoresis with electrochemical detection using an epoxy‐based molding method to embed multiple electrode materials http://www.medworm.com/index.php?rid=5374707&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100433 AbstractThis paper describes the use of epoxy‐encapsulated electrodes to integrate microchip‐based electrophoresis with electrochemical detection. Devices with various electrode combinations can easily be developed. This includes a palladium decoupler with a downstream working electrode material of either gold, mercury/gold, platinum, glassy carbon, or a carbon fiber bundle. Additional device components such as the platinum wires for the electrophoresis separation and the counter electrode for detection can also be integrated into the epoxy base. The effect of the decoupler configuration was studied in terms of the separation performance, detector noise, and the ability to analyze samples of a high ionic strength. The ability of both glassy carbon and carbon fiber bundle electrodes to ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5374707 Tue, 01 Nov 2011 04:00:00 +0100 5374707 Integrated continuous flow polymerase chain reaction and micro‐capillary electrophoresis system with bioaffinity preconcentration http://www.medworm.com/index.php?rid=5374711&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100274 AbstractAn integrated and modular DNA analysis system is reported that consists of two modules: (i) A continuous flow polymerase chain reaction (CFPCR) module fabricated in a high Tg (150°C) polycarbonate substrate in which selected gene fragments were amplified using biotin and fluorescently labeled primers accomplished by continuously shuttling small packets of PCR reagents and template through isothermal zones as opposed to heating and cooling large thermal masses typically performed in batch‐type thermal reactors. (ii) μCE (micro‐capillary electrophoresis) module fabricated in poly(methylmethacrylate) (PMMA), which utilized a bioaffinity selection and purification bed (2.9 μL) to preconcentrate and purify the PCR products generated from the CFPCR module prior to electrophoreti... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5374711 Mon, 31 Oct 2011 04:00:00 +0100 5374711 Surface instability of a thin electrolyte film undergoing coupled electroosmotic and electrophoretic flows in a microfluidic channel http://www.medworm.com/index.php?rid=5374710&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100306 AbstractWe consider the stability of a thin liquid film with a free charged surface resting on a solid charged substrate by performing a general Orr–Sommerfeld (O‐S) analysis complemented by a long‐wave (LW) analysis. An externally applied field generates an electroosmotic flow (EOF) near the solid substrate and an electrophoretic flow (EPF) at the free surface. The EPF retards the EOF when both the surfaces have the same sign of the potential and can even lead to the flow reversal in a part of the film. In conjunction with the hydrodynamic stress, the Maxwell stress is also considered in the problem formulation. The electrokinetic potential at the liquid–air and solid–liquid interfaces is modelled by the Poisson–Boltzmann equation with the Debye–Hückel approximation. The O... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5374710 Mon, 31 Oct 2011 04:00:00 +0100 5374710 Microfluidic devices with disposable enzyme electrode for electrochemical monitoring of glucose concentrations http://www.medworm.com/index.php?rid=5374709&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100355 This article describes the fabrication of tube‐like microchannels made of UV curable polymer on a glass substrate and the device assembling with a disposable enzyme‐working electrode for high‐sensitivity electrochemical detection. While both reference and counter electrodes are patterned on the surface of the glass substrate, the working electrode is flipped on the top of the channel with an open access, providing a face‐to‐face probing configuration. When the enzyme electrode is contaminated or degraded, it can be easily replaced by a new one, keeping the main body of the device and the detection schema unchanged. Using glucose oxidase‐coated gold electrodes, we were able to determine a linear amperometry response to the glucose concentrations in the range of 2–16 mM. By r... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5374709 Mon, 31 Oct 2011 04:00:00 +0100 5374709 Fabrication optimization of a miniaturized array device for cell‐free protein synthesis http://www.medworm.com/index.php?rid=5374708&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201100376 We report here a miniaturized CFPS device that addresses these challenges. The cost saving was achieved by miniaturization, which reduced the reagent consumption by two orders of magnitude. The protein synthesis yield was enhanced by prolonging CFPS reactions through continuous supply of reactants (e.g. nutrients and energy components). The reactants were contained in a feeding solution, which was replenished through a nanoporous membrane and microchannel. The design of the miniaturized device was optimized by running continuous‐exchange CFPS in devices with a variation in the type of membrane, the size of the exchange interface, and the volume ratio of the reaction solution to the feeding solution. The effects of these design variations on the protein synthesis yield have been studied. ... Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5374708 Mon, 31 Oct 2011 04:00:00 +0100 5374708 Meetings Diary http://www.medworm.com/index.php?rid=5355044&cid=s_33767_60_f&fid=33767&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Felps.201190102 (Source: Electrophoresis) Electrophoresis journals http://www.medworm.com/rss/comments.php?id=5355044 Thu, 27 Oct 2011 23:23:49 +0100 5355044