Highly sensitive detection of monosaccharides on microchip electrophoresis using pH discontinuous solution system.

We improved the detection sensitivity of neutral and amino monosaccharides labeled with 2-aminoacridone by a factor of 19.6-48.7 and 44.

Light-triggered thermoelectric conversion based on a carbon nanotube-polymer hybrid gel.

Lights? Nanotubes? Action! A hydrogel comprising lysozymes, poly(ethylene glycol), phospholipids, and functionalized single-walled carbon nanotubes is employed for light-driven thermoelectric conversion. A photoinduced thermoelectric conversion module based on the hydrogel functions as a novel electric power generator (see image). This concept may find application in various industries, such as robotics and aerospace engineering.

Laser-triggered carbon nanotube microdevice for remote control of biocatalytic reactions.

We have developed a near-infrared laser-driven carbon nanotube (CNT) microdevice. Powerful photo-exothermy of CNT was coupled with a microdevice for remote control of temperature-dependent biocatalytic transformations. We succeeded in ultrafast temperature change (<0.

Use of a heterogeneous buffer combination in microchip electrophoresis for high-resolution separation by on-line concentration of DNA samples.

We have developed a novel high-resolution separation technique of DNA fragments in a heterogeneous combination of a sample buffer and a separation buffer. The use of a heterogeneous buffer combination is a simple method for on-line concentration of DNA fragments, in which a sample buffer is simply exchanged with one including taurine anions. The mobility of taurine anions, co-ions for DNA, is lower than the that of acetate anions in a separation buffer.

BMP2-induced gene profiling in dental epithelial cell line.

Tooth development is regulated by epithelial-mesenchymal interactions and their reciprocal molecular signaling. Bone morphogenetic protein 2 (BMP2) is known as one of the inducers for tooth development. To analyze the molecular mechanisms of BMP2 on ameloblast differentiation (amelogenesis), we performed microarray analyses using rat dental epithelial cell line, HAT-7.

Sizing of single globular DNA molecules by using a circular acceleration technique with laser trapping.

We describe a method for in situ sizing individual huge DNA molecules by laser trapping. Single DNA molecules are reversibly transformed, without mechanical fragmentation of fragile huge-sized DNA, from their random coil state into their globular state induced by condensing agents poly(ethylene glycol) and Mg(2+). With the use of a globular DNA molecule folded by condensation, the critical velocity of the circularly accelerated single globular DNA molecule by laser trapping was found to be proportional to the size of the DNA.

Photoinduced antiviral carbon nanohorns.

Nanocarbons, such as carbon nanohorns (CNH) and carbon nanotubes, are materials of interest in many fields of science and technology because of their remarkable physical properties. We report here a novel approach for using NIR laser-driven CNH as an antiviral agent. NIR laser-driven functional CNH complexes could open the way to a new range of antiviral materials.

Genome wide expression analysis of white blood cells and liver of pre-diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats using a cDNA microarray.

In a prior study, we reported on a significant decrease in calpain10 gene expression in white blood cells (WBC) as well as the major insulin-target tissues including liver and adipose tissue, before the onset of diabetes in Otsuka Long-Evans Tokushima Fatty (OLETF) rats. In this study, we extended our hypothesis that some type 2 diabetes mellitus (NIDDM) susceptible genes are up/down-regulated before the onset in WBC of OLETF rats, reflecting their up/down-regulation in major insulin-target tissues, such as the liver. We tested this hypothesis using rat cDNA microarrays.

Conformational separation of monosaccharides of glycoproteins labeled with 2-aminoacrydone using microchip electrophoresis.

The conformational separation of monosaccharides labeled with fluorescent 2-aminoacrydone (AMAC) was performed by electrophoresis on a plastic microchip with light-emitting diode confocal fluorescence detection. The AMAC-labeled five neutral monosaccharide mixture (D-glucose (Glc), D-mannose, D-galactose, L-fucose, and D-xylose) or two amino monosaccharide mixture (N-acetyl-D-glucosamine and N-acetyl-D-galactosamine) were well separated at pH 8.5 and 0.

On-line microdevice for stress proteomics.

The handling of the cells or tissues is essential for proteomics research or drug screening, where labor is not avoidable. The steps of cell wash, protein extraction, protein denaturing are complicated procedures in conventional method using centrifugation and pipetting in the laboratory. This is the bottle-neck for proteome research.

High-speed separation of proteins by microchip electrophoresis using a polyethylene glycol-coated plastic chip with a sodium dodecyl sulfate-linear polyacrylamide solution.

In this paper, we describe a method for size-based electrophoretic separation of sodium dodecyl sulfate (SDS)-protein complexes on a polymethyl methacrylate (PMMA) microchip, using a separation buffer solution containing SDS and linear polyacrylamide as a sieving matrix. We developed optimum conditions under which protein separations can be performed, using polyethylene glycol (PEG)-coated polymer microchips and electrokinetic sample injection. We studied the performance of protein separations on the PEG-coated PMMA microchip.

Microchip electrophoretic protein separation using electroosmotic flow induced by dynamic sodium dodecyl sulfate-coating of uncoated plastic chips.

Separation of sodium dodecyl sulfate (SDS)-protein complexes is difficult on plastic microchips due to protein adsorption onto the wall. In this paper, we elucidated the reasons for the difficulties in separating SDS-protein complexes on plastic microchips, and we then demonstrated an effective method for separating proteins using polymethyl methacrylate (PMMA) microchips. Separation difficulties were found to be dependent on adsorption of SDS onto the hydrophobic surface of the channel, by which cathodic electroosmotic flow (EOF; reversed flow) was generated.

A design of nanosized PEGylated-latex mixed polymer solution for microchip electrophoresis.

We report here advanced microchip electrophoresis using a nanoparticle doped polymer solution that enables greater separation of DNA. The proposed system is simple and effective without any new apparatus or complicated procedures. Various amounts and sizes (80 nm, 110 nm, and 193 nm) of polymer nanoparticle solutions (PEGylated-latex) were mixed with a conventional polymer solution for microchip electrophoresis.

Influence of the pH on separating DNA by high-speed microchip electrophoresis.

Various factors are critical in resolving DNA molecules at high speed, including the separation medium, concentration, composition, and pH of the buffer, as well as the electric field strength. To this study, considered the composition of a buffer and the difference in the pH, while paying attention to whether the separation ability changes in the microchip electrophoresis of DNA. DNA separation was particularly affected by both the buffer composition and the pH.