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Nucleation and Growth of Crystalline Grains in RF-Sputtered TiO2 FilmsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Amorphous TiO2 thin films were radio frequency sputtered onto siliconmonoxide and carbon support films on molybdenum transmission electron microscope (TEM) grids and observed during in situ annealing in a TEM heating stage at 250∘C. The evolution of crystallization is consistent with a classical model of homogeneous nucleation and isotropic grain growth. The two-dimensional grain morphology of the TEM foil allowed straightforward recognition of amorphous and crystallized regions of the films, for measurement of crystalline volume fraction and grain number density. By assuming that the kinetic parameters remain const...
Source: Research Letters in Nanotechnology - October 12, 2009 Category: Nanotechnology Source Type: journals

Protein Fibrillar Hydrogels for three-Dimensional Tissue EngineeringEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Protein self-assembly into highly ordered fibrillar aggregates has attracted increasing attention over recent years, due primarily to its association with disease states such as Alzheimer's. More recently, however, research has focused on understanding the generic behavior of protein self-assembly where fibrillation is typically induced under harsh conditions of low pH and/or high temperature. Moreover the inherent properties of these fibrils, including their nanoscale dimension, environmental responsiveness, and biological compatibility, are attracting substantial interest for exploiting these fibrils for the creation...
Source: Research Letters in Nanotechnology - August 31, 2009 Category: Nanotechnology Source Type: journals

Microporosity Development of Herringbone Carbon Nanofibers by RbOH Chemical ActivationEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The influence of different activation conditions, including activating agent/CNFs ratio, activation temperature, and He flow rate, on the pore structure development of herringbone carbon nanofibers (CNFs) was studied. The best results of activated CNFs with larger specific surface area can be achieved using the following optimized factors: RbOH/CNFs ratio = 4/1, activation temperature = 900∘C ,and a He flow rate = 850 ml/min. The optimization of these three factors leads to high CNFs micropore volume, being the surface area increased by a factor of 3 compared to the raw CNFs. It is important to note that only...
Source: Research Letters in Nanotechnology - July 28, 2009 Category: Nanotechnology Source Type: journals

Processing and Electrochemical Property Characterization of Nanoporous Electrodes for Sustainable Energy ApplicationsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Preparation and electrocatalytic reactions of nanoporous materials in biodegradable fluids were studied. Electrochemical etching was conducted to selectively extract metallic elements from alloys to form porous structures. Electrocatalytic properties of the porous electrodes were characterized. Comparative studies on the electrochemical activities of the nanoporous metallic electrodes with bulk metallic wire catalysts were performed. It is found that the current density at the nanoporous electrode is three times higher than that of the bulk electrode. (Source: Research Letters in Nanotechnology)
Source: Research Letters in Nanotechnology - July 12, 2009 Category: Nanotechnology Source Type: journals

Development of SBR-Nanoclay Composites with Epoxidized Natural Rubber as CompatibilizerEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The significant factor that determines the improvement of properties in rubber by the incorporation of nanoclay is its distribution in the rubber matrix. The simple mixing of nonpolar rubber and organically modified nanoclay will not contribute for the good dispersion of nanofiller in the rubbery matrix. Hence a polar rubber like epoxidized natural rubber (ENR) can be used as a compatibilizer in order to obtain a better dispersion of the nanoclay in the matrix polymer. Epoxidized natural rubber and organically modified nanoclay composites (EC) were prepared by solution mixing. The nanoclay employed in this study is Cloisit...
Source: Research Letters in Nanotechnology - July 8, 2009 Category: Nanotechnology Source Type: journals

Patterning of Gold Nanoparticles on DNA Self-Assembled ScaffoldsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
We report a method of patterning the 1D and 2D arrays of gold nanoparticles on the DNA self-assembled scaffolds. The 5 nm gold nanoparticle was well positioned at the center of each 4×4 tile motif of the DNA scaffold. The precisely located gold particles can form 1D and 2D arrays. This controllable scaffolding technology may become a promising tool for nanoscaled fabrication of electronics and photonic devices. (Source: Research Letters in Nanotechnology)
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Assembly/Disassembly of DNA-Au Nanoparticles: A Strategy of InterventionEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This report describes the viability of a strategy for manipulating the assembly/disassembly processes of DNA-Au nanoparticles by molecular intervention. Using the temperature-induced assembly and disassembly processes of DNAs and gold nanoparticles as a model system, the introduction of a molecular recognition probe is demonstrated to lead to the intervention of the assembly/disassembly processes depending on its specific biorecognition. This process can be detected by monitoring the change in the optical properties of gold nanoparticles and their DNA assemblies. Implications of the preliminary results to exploration of th...
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Charge Transport Phenomena in Peptide Molecular JunctionsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Inelastic electron tunneling spectroscopy (IETS) is a valuable in situ spectroscopic analysis technique that provides a direct portrait of the electron transport properties of a molecular species. In the past, IETS has been applied to small molecules. Using self-assembled nanoelectronic junctions, IETS was performed for the first time on a large polypeptide protein peptide in the phosphorylated and native form, yielding interpretable spectra. A reproducible 10-fold shift of the I/V characteristics of the peptide was observed upon phosphorylation. Phosphorylation can be utilized as a site-specific modification to alter pept...
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Gold and TiO2Nanostructurated Surfaces for Assembling of Electrochemical BiosensorsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Devices based on nanomaterials are emerging as a powerful and general class of ultrasensitive sensors for the direct detection of biological and chemical species. In this work, we report the preparation and the full characterization of nanomaterials such as gold nanowires and TiO2 nanostructured films to be used for assembling of electrochemical biosensors. Gold nanowires were prepared by electroless deposition within the pores of polycarbonate particle track-etched membranes (PTMs). Glucose oxidase was deposited onto the nanowires using self-assembling monolayer as an anchor layer for the enzyme molecules. Finally, cyclic...
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Effect of Ammonium Nitrate on Nanoparticle Size ReductionEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Ammonium nitrate was added to the spraying solution as a foaming agent to reduce the particle size of nanoparticles synthesized in the spray-pyrolysis process. Ammonium nitrate was effective in breaking the aerosol droplet size and generating nanoparticles that were of approximately one order-of-magnitude (from 200 to 20 nm) smaller diameter than those created in the absence of ammonium nitrate in the feed solution. This technique makes it possible to control the particle diameter of metallic nanoparticles below 20 nm. (Source: Research Letters in Nanotechnology)
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Angular Dependence of Fluorescence Emission from Quantum Dots inside a Photonic CrystalEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The fluorescence of emitters embedded in a photonic crystal is known to be inhibited by the presence of an incomplete photonic band gap or pseudogap acting in their emission range. Here, we present a study of the angular dependence of the fluorescence emission of emitters embedded in a photonic crystal. Our results clearly show an angular dependence of the fluorescence emission, which is caused by the presence of an incomplete 3D band gap. (Source: Research Letters in Nanotechnology)
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Apparent Enhanced Solubility of Single-Wall Carbon Nanotubes in a Deuterated Acid MixtureEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
An apparent enhanced solubility of single-wall carbon nanotubes (SWNTs) in the deuterated form of the standard 3 : 1 sulfuric (H2SO4) to nitric (HNO3) acid mixture treatment is reported and attributed to the stronger interaction of deuterium bonds with the single-wall carbon nanotube surface. UV-Visible spectroscopy was used to characterize the apparent enhanced solubility of the SWNTs treated in deuterated forms of the acid mixture in comparison to the standard acid mix, while FTIR was used to analyze the nature of the functional groups generated on the SWNTs as a result of the different acid treatments. The apparent enha...
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Iron Oxide Doped Alumina-Zirconia Nanoparticle Synthesis by Liquid Flame Spray from Metal Organic PrecursorsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The liquid flame spray (LFS) method was used to make iron oxide doped alumina-zirconia nanoparticles. Nanoparticles were generated using a turbulent, high-temperature (Tmax⁡∼3000 K) H2-O2 flame. The precursors were aluminium-isopropoxide, zirconium-n-propoxide, and ferrocene in xylene solution. The solution was atomized into micron-sized droplets by high velocity H2 flow and introduced into the flame where nanoparticles were formed. The particle morphology, size, phase, and chemical composition were determined by TEM, XRD, XPS, and N2-adsorption measurements. The collected particulate material consists...
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Achieving High Aspect Ratio of Track Length to Width in Molds for Discrete Track Recording MediaEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Discrete track media (DTM) fabricated by nanoimprint lithography (NIL) is considered as a potential technology for future hard disk drives (HDD). In the fabrication of a master mold for NIL, patterning the resist tracks with a narrow distribution in the width is the first critical step. This paper reports the challenges involved in the fabrication of high aspect ratio discrete tracks on Polymethylmethacrylate (PMMA) resist by means of electron beam lithography. It was observed that fabrication parameters applied for successful patterning of discrete tracks in nanoscale length were not directly suitable for the patterning o...
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Single-Walled Carbon Nanotubes as Fluorescence Biosensors for Pathogen Recognition in Water SystemsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The possibility of using single-walled carbon nanotubes (SWCNTs) aggregates as fluorescence sensors for pathogen recognition in drinking water treatment applications has been studied. Batch adsorption study is conducted to adsorb large concentrations of Staphylococcus aureus aureus SH 1000 and Escherichia coli pKV-11 on single-walled carbon nanotubes. Subsequently the immobilized bacteria are detected with confocal microscopy by coating the nanotubes with fluorescence emitting antibodies. The Freundlich adsorption equilibrium constant (k) for S.aureus and E.coli determined from batch adsorption study was found to be 9�...
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Synthesis of PET-PLA/Drug Nanoparticles and Their Effect with Gold Nanoparticles for Controlled Drug Release in Cancer ChemotherapyEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Polyethylene terephthalate-polylactic acid copolymer (PET-PLA) was synthesized from bis (2-hydroxyethyl terephthalate) and L-lactic acid oligomer in the presence of manganese antimony glycoxide as a catalyst. The synthesized PET-PLA copolymer was used for controlled drug release systems with gold nanoparticles. Fluorouracil containing PET-PLA nanocapsules was prepared in the presence of gold nanoparticles by solvent evaporation method. The morphologies of the nanocapsules were characterized using scanning electron microscopy and transmission electron microscopy. Controlled release of Fu and Fu@Au was carried out in 0.1...
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Analysis of Polymorphic Nanocrystals of TiO2 by X-Ray Rietveld Refinement and High-Resolution Transmission Electron Microscopy: Acetaldehyde DecompositionEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this work, TiO2 nanocrystals were synthesized by the sol-gel method. These materials were annealed at 200 and 500∘C; and characterized by the XRD-Rietveld refinement; and by BET and TEM. As for the low-temperature-treated sample (200∘C), nanocrystals with small crystallite sizes (7 nm) and high abundance of anatase, coexisting with the brookite phase, were obtained. Meanwhile, the sample annealed at 500∘C showed an increased crystallite size (22 nm) and an important polymorphic increment. The sample annealed at 200∘C showed a high activity in the photocatalytic decomposition of ...
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Photo- and Electrochromic Properties of Activated Reactive Evaporated MoO3 Thin Films Grown on Flexible SubstratesEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The molybdenum trioxide (MoO3) thin films were grown onto ITO-coated flexible Kapton substrates using plasma assisted activated reactive evaporation technique. The film depositions were carried out at constant glow power and oxygen partial pressures of 8 W and 1×10−3 Torr, respectively. The influence of substrate temperature on the microstructural and optical properties was investigated. The MoO3 thin films prepared at a substrate temperature of 523 K were found to be composed of uniformly distributed nanosized grains with an orthorhombic structure of α-MoO3. These nanocrystalline MoO...
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

A Method for Fabricating Arrays of Nanopatterns with the Feature Size beyond Diffraction LimitEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
A convenient lithographic technique is proposed in this paper, which can be used to produce subdiffraction-limit arrays of nanopatterns over large areas (about several square centimeters). An array of polystyrene spheres (PS) is arranged on the surface of a layer of silver which has a thickness of about tens of nanometers. With the normal illumination light of wavelength 365 nm perpendicular to the substrate, PS can generate an array of optical patterns with high intensity at their contact points with silver. By designing the silver slab, the evanescent waves that carry subwavelength information about the optical pa...
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Growth of Functional FeTi Clusters Covered with Carbon LayerEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
FeTi clusters with a diameter of less than 10 nm and covered with a graphitic layer have been preferentially produced in an H2 gas atmosphere at pressures of 10 and 26.6 kPa by the simultaneous evaporation of Fe and Ti wires from a concave carbon boat. To compare this result with cluster formation in an inert gas atmosphere, the result for an Ar gas pressure of 10 kPa is also discussed. The formation of disordered FeNi clusters predominately took place in an H2 gas atmosphere. (Source: Research Letters in Nanotechnology)
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Studies on Calcium Ion Selectivity of ZnO Nanowire Sensors Using Ionophore Membrane CoatingsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Zinc oxide nanorods with 100 nm diameter and 900 nm length were grown on the surface of a silver wire (0.25 mm in diameter) with the aim to produce electrochemical nanosensors. It is shown that the ZnO nanorods exhibit a Ca2+-dependent electrochemical potentiometric behavior in an aqueous solution. The potential difference was found to be linear over a large logarithmic concentration range (1 μM to 0.1 M) using Ag/AgCl as a reference electrode and the response time was less than one minute. In order to adapt the sensors for calcium ion measurements in biological fluids with suffici...
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Nanostructural Formation of Pd-Co Bimetallic Complex on HOPG Surfaces: XPS and AFM StudiesEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
A new single source approach was developed to synthesize Pd-Co nanoparticles using a bimetallic compound, [Et3NH]2[CoPd2(μ-4-I-3,5-Me2pz)4Cl4] (CoPd2), as a molecular precursor to obtain dispersed catalyst on highly ordered pyrolytic graphite (HOPG) surface, in view of preparing oxygen reduction catalysts for low temperature fuel cells. X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) techniques were employed to characterize the nanostructure formations and to determine the composition and morphology of the complex on the HOPG. Results of high resolution XPS analysis (HR-XPS...
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Effect of Premelting on Conductivity of DNA-Lipid FilmsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
We have measured temperature-dependent (between 20 and 80∘C) electrical conductivity and molecular structure (Raman spectroscopy) of DNA-lipid cast film. Our findings show that the conductivity is strongly influenced by premelting effects in the molecular structure starting near physiological temperatures (∼40∘C), prior to the global DNA denaturation. (Source: Research Letters in Nanotechnology)
Source: Research Letters in Nanotechnology - June 10, 2009 Category: Nanotechnology Source Type: journals

Nanostructural Formation of Pd-Co Bimetallic Complex on HOPG Surfaces: XPS and AFM StudiesEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
A new single source approach was developed to synthesize Pd-Co nanoparticles using a bimetallic compound, [Et3NH]2[CoPd2(μ-4-I-3,5-Me2pz)4Cl4] (CoPd2), as a molecular precursor to obtain dispersed catalyst on highly ordered pyrolytic graphite (HOPG) surface, in view of preparing oxygen reduction catalysts for low temperature fuel cells. X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) techniques were employed to characterize the nanostructure formations and to determine the composition and morphology of the complex on the HOPG. Results of high resolution XPS analysis (HR-XPS...
Source: Research Letters in Nanotechnology - April 5, 2009 Category: Nanotechnology Source Type: journals

Effect of Premelting on Conductivity of DNA-Lipid FilmsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
We have measured temperature-dependent (between 20 and 80∘C) electrical conductivity and molecular structure (Raman spectroscopy) of DNA-lipid cast film. Our findings show that the conductivity is strongly influenced by premelting effects in the molecular structure starting near physiological temperatures (∼40∘C), prior to the global DNA denaturation. (Source: Research Letters in Nanotechnology)
Source: Research Letters in Nanotechnology - April 5, 2009 Category: Nanotechnology Source Type: journals

Studies on Calcium Ion Selectivity of ZnO Nanowire Sensors Using Ionophore Membrane CoatingsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Zinc oxide nanorods with 100 nm diameter and 900 nm length were grown on the surface of a silver wire (0.25 mm in diameter) with the aim to produce electrochemical nanosensors. It is shown that the ZnO nanorods exhibit a Ca2+-dependent electrochemical potentiometric behavior in an aqueous solution. The potential difference was found to be linear over a large logarithmic concentration range (1 μM to 0.1 M) using Ag/AgCl as a reference electrode and the response time was less than one minute. In order to adapt the sensors for calcium ion measurements in biological fluids with suffici...
Source: Research Letters in Nanotechnology - January 8, 2009 Category: Nanotechnology Source Type: journals

Growth of Functional FeTi Clusters Covered with Carbon LayerEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
FeTi clusters with a diameter of less than 10 nm and covered with a graphitic layer have been preferentially produced in an H2 gas atmosphere at pressures of 10 and 26.6 kPa by the simultaneous evaporation of Fe and Ti wires from a concave carbon boat. To compare this result with cluster formation in an inert gas atmosphere, the result for an Ar gas pressure of 10 kPa is also discussed. The formation of disordered FeNi clusters predominately took place in an H2 gas atmosphere. (Source: Research Letters in Nanotechnology)
Source: Research Letters in Nanotechnology - December 22, 2008 Category: Nanotechnology Source Type: journals

A Method for Fabricating Arrays of Nanopatterns with the Feature Size beyond Diffraction LimitEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
A convenient lithographic technique is proposed in this paper, which can be used to produce subdiffraction-limit arrays of nanopatterns over large areas (about several square centimeters). An array of polystyrene spheres (PS) is arranged on the surface of a layer of silver which has a thickness of about tens of nanometers. With the normal illumination light of wavelength 365 nm perpendicular to the substrate, PS can generate an array of optical patterns with high intensity at their contact points with silver. By designing the silver slab, the evanescent waves that carry subwavelength information about the optical pa...
Source: Research Letters in Nanotechnology - December 15, 2008 Category: Nanotechnology Source Type: journals

Photo- and Electrochromic Properties of Activated Reactive Evaporated MoO3 Thin Films Grown on Flexible SubstratesEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The molybdenum trioxide (MoO3) thin films were grown onto ITO-coated flexible Kapton substrates using plasma assisted activated reactive evaporation technique. The film depositions were carried out at constant glow power and oxygen partial pressures of 8 W and 1×10−3 Torr, respectively. The influence of substrate temperature on the microstructural and optical properties was investigated. The MoO3 thin films prepared at a substrate temperature of 523 K were found to be composed of uniformly distributed nanosized grains with an orthorhombic structure of α-MoO3. These nanocrystalline MoO...
Source: Research Letters in Nanotechnology - December 4, 2008 Category: Nanotechnology Source Type: journals

Analysis of Polymorphic Nanocrystals of TiO2 by X-Ray Rietveld Refinement and High-Resolution Transmission Electron Microscopy: Acetaldehyde DecompositionEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
In this work, TiO2 nanocrystals were synthesized by the sol-gel method. These materials were annealed at 200 and 500∘C; and characterized by the XRD-Rietveld refinement; and by BET and TEM. As for the low-temperature-treated sample (200∘C), nanocrystals with small crystallite sizes (7 nm) and high abundance of anatase, coexisting with the brookite phase, were obtained. Meanwhile, the sample annealed at 500∘C showed an increased crystallite size (22 nm) and an important polymorphic increment. The sample annealed at 200∘C showed a high activity in the photocatalytic decomposition of ...
Source: Research Letters in Nanotechnology - August 4, 2008 Category: Nanotechnology Source Type: journals

Patterning of Gold Nanoparticles on DNA Self-Assembled ScaffoldsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
We report a method of patterning the 1D and 2D arrays of gold nanoparticles on the DNA self-assembled scaffolds. The 5 nm gold nanoparticle was well positioned at the center of each 4×4 tile motif of the DNA scaffold. The precisely located gold particles can form 1D and 2D arrays. This controllable scaffolding technology may become a promising tool for nanoscaled fabrication of electronics and photonic devices. (Source: Research Letters in Nanotechnology)
Source: Research Letters in Nanotechnology - July 14, 2008 Category: Nanotechnology Source Type: journals

Assembly/Disassembly of DNA-Au Nanoparticles: A Strategy of InterventionEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
This report describes the viability of a strategy for manipulating the assembly/disassembly processes of DNA-Au nanoparticles by molecular intervention. Using the temperature-induced assembly and disassembly processes of DNAs and gold nanoparticles as a model system, the introduction of a molecular recognition probe is demonstrated to lead to the intervention of the assembly/disassembly processes depending on its specific biorecognition. This process can be detected by monitoring the change in the optical properties of gold nanoparticles and their DNA assemblies. Implications of the preliminary results to exploration of th...
Source: Research Letters in Nanotechnology - July 14, 2008 Category: Nanotechnology Source Type: journals

Charge Transport Phenomena in Peptide Molecular JunctionsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Inelastic electron tunneling spectroscopy (IETS) is a valuable in situ spectroscopic analysis technique that provides a direct portrait of the electron transport properties of a molecular species. In the past, IETS has been applied to small molecules. Using self-assembled nanoelectronic junctions, IETS was performed for the first time on a large polypeptide protein peptide in the phosphorylated and native form, yielding interpretable spectra. A reproducible 10-fold shift of the I/V characteristics of the peptide was observed upon phosphorylation. Phosphorylation can be utilized as a site-specific modification to alter pept...
Source: Research Letters in Nanotechnology - July 14, 2008 Category: Nanotechnology Source Type: journals

Gold and TiO2Nanostructurated Surfaces for Assembling of Electrochemical BiosensorsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Devices based on nanomaterials are emerging as a powerful and general class of ultrasensitive sensors for the direct detection of biological and chemical species. In this work, we report the preparation and the full characterization of nanomaterials such as gold nanowires and TiO2 nanostructured films to be used for assembling of electrochemical biosensors. Gold nanowires were prepared by electroless deposition within the pores of polycarbonate particle track-etched membranes (PTMs). Glucose oxidase was deposited onto the nanowires using self-assembling monolayer as an anchor layer for the enzyme molecules. Finally, cyclic...
Source: Research Letters in Nanotechnology - July 14, 2008 Category: Nanotechnology Source Type: journals

Effect of Ammonium Nitrate on Nanoparticle Size ReductionEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Ammonium nitrate was added to the spraying solution as a foaming agent to reduce the particle size of nanoparticles synthesized in the spray-pyrolysis process. Ammonium nitrate was effective in breaking the aerosol droplet size and generating nanoparticles that were of approximately one order-of-magnitude (from 200 to 20 nm) smaller diameter than those created in the absence of ammonium nitrate in the feed solution. This technique makes it possible to control the particle diameter of metallic nanoparticles below 20 nm. (Source: Research Letters in Nanotechnology)
Source: Research Letters in Nanotechnology - July 14, 2008 Category: Nanotechnology Source Type: journals

Angular Dependence of Fluorescence Emission from Quantum Dots inside a Photonic CrystalEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The fluorescence of emitters embedded in a photonic crystal is known to be inhibited by the presence of an incomplete photonic band gap or pseudogap acting in their emission range. Here, we present a study of the angular dependence of the fluorescence emission of emitters embedded in a photonic crystal. Our results clearly show an angular dependence of the fluorescence emission, which is caused by the presence of an incomplete 3D band gap. (Source: Research Letters in Nanotechnology)
Source: Research Letters in Nanotechnology - July 14, 2008 Category: Nanotechnology Source Type: journals

Apparent Enhanced Solubility of Single-Wall Carbon Nanotubes in a Deuterated Acid MixtureEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
An apparent enhanced solubility of single-wall carbon nanotubes (SWNTs) in the deuterated form of the standard 3 : 1 sulfuric (H2SO4) to nitric (HNO3) acid mixture treatment is reported and attributed to the stronger interaction of deuterium bonds with the single-wall carbon nanotube surface. UV-Visible spectroscopy was used to characterize the apparent enhanced solubility of the SWNTs treated in deuterated forms of the acid mixture in comparison to the standard acid mix, while FTIR was used to analyze the nature of the functional groups generated on the SWNTs as a result of the different acid treatments. The apparent enha...
Source: Research Letters in Nanotechnology - July 14, 2008 Category: Nanotechnology Source Type: journals

Iron Oxide Doped Alumina-Zirconia Nanoparticle Synthesis by Liquid Flame Spray from Metal Organic PrecursorsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The liquid flame spray (LFS) method was used to make iron oxide doped alumina-zirconia nanoparticles. Nanoparticles were generated using a turbulent, high-temperature (Tmax⁡∼3000 K) H2-O2 flame. The precursors were aluminium-isopropoxide, zirconium-n-propoxide, and ferrocene in xylene solution. The solution was atomized into micron-sized droplets by high velocity H2 flow and introduced into the flame where nanoparticles were formed. The particle morphology, size, phase, and chemical composition were determined by TEM, XRD, XPS, and N2-adsorption measurements. The collected particulate material consists...
Source: Research Letters in Nanotechnology - July 14, 2008 Category: Nanotechnology Source Type: journals

Achieving High Aspect Ratio of Track Length to Width in Molds for Discrete Track Recording MediaEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Discrete track media (DTM) fabricated by nanoimprint lithography (NIL) is considered as a potential technology for future hard disk drives (HDD). In the fabrication of a master mold for NIL, patterning the resist tracks with a narrow distribution in the width is the first critical step. This paper reports the challenges involved in the fabrication of high aspect ratio discrete tracks on Polymethylmethacrylate (PMMA) resist by means of electron beam lithography. It was observed that fabrication parameters applied for successful patterning of discrete tracks in nanoscale length were not directly suitable for the patterning o...
Source: Research Letters in Nanotechnology - July 14, 2008 Category: Nanotechnology Source Type: journals

Single-Walled Carbon Nanotubes as Fluorescence Biosensors for Pathogen Recognition in Water SystemsEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
The possibility of using single-walled carbon nanotubes (SWCNTs) aggregates as fluorescence sensors for pathogen recognition in drinking water treatment applications has been studied. Batch adsorption study is conducted to adsorb large concentrations of Staphylococcus aureus aureus SH 1000 and Escherichia coli pKV-11 on single-walled carbon nanotubes. Subsequently the immobilized bacteria are detected with confocal microscopy by coating the nanotubes with fluorescence emitting antibodies. The Freundlich adsorption equilibrium constant (k) for S.aureus and E.coli determined from batch adsorption study was found to be 9�...
Source: Research Letters in Nanotechnology - July 14, 2008 Category: Nanotechnology Source Type: journals

Synthesis of PET-PLA/Drug Nanoparticles and Their Effect with Gold Nanoparticles for Controlled Drug Release in Cancer ChemotherapyEmail this article to a colleague. Save this article to My Clippings. Discuss or comment on this article.
Polyethylene terephthalate-polylactic acid copolymer (PET-PLA) was synthesized from bis (2-hydroxyethyl terephthalate) and L-lactic acid oligomer in the presence of manganese antimony glycoxide as a catalyst. The synthesized PET-PLA copolymer was used for controlled drug release systems with gold nanoparticles. Fluorouracil containing PET-PLA nanocapsules was prepared in the presence of gold nanoparticles by solvent evaporation method. The morphologies of the nanocapsules were characterized using scanning electron microscopy and transmission electron microscopy. Controlled release of Fu and Fu@Au was carried out in 0.1...
Source: Research Letters in Nanotechnology - July 14, 2008 Category: Nanotechnology Source Type: journals