Novel separation mode of HPLC based on phase-separation multiphase flow.

A novel separation mode for high-performance liquid chromatography (HPLC) is proposed based on phase-separation multiphase flow. A commercially available HPLC system was used with a packed-separation column of octadecyl-silica (ODS)-modified particles. Water/acetonitrile/ethyl acetate ternary mixed solutions, (a) 1:8:1, (b) 1:3:1, and (c) 16:3:1 (v/v/v), were delivered into the system as an eluent at 20 and 5 °C.

Periodicity in ultrasonic atomization involving beads-fountain oscillations and mist generation: Effects of driving frequency.

Ultrasonic atomization induced by high driving frequency, generally on the order of 1 MHz or higher, could involve a liquid fountain in the form of a corrugated jet, or a chain of "beads" of submillimeter diameter in contact. This study concerns dynamics/instability of such beads fountain, observed under lower input power density (≤ 6 W/cm) of the "flat" ultrasound transducer with a "regulating" nozzle equipped, exhibiting time-varying characteristics with certain periodicity. High-speed, high-resolution images are processed for quantitative elucidation: frequency analysis (fast Fourier transform) and time-frequency analysis (discrete wavelet transform) are employed, respectively, to evaluate dominant frequencies of beads-surface oscillations and to reveal factor(s) triggering mist emergence.

Consecutive Sample Injection Analysis in Tube Radial Distribution Chromatography.

Tube radial distribution chromatography based on the tube radial distribution flow, or annular flow, in an open-tubular capillary has been reported, where the annular flow is created through phase-separation multiphase flow. We have proposed the first-ever procedure for consecutive sample injection analysis using chromatography. In basic terms, a commercially available HPLC system could be used with a sample injector (0.

Phase Separation and Collection of Annular Flow by Phase Transformation.

A polyethylene glycol/citrate mixed solution was fed into a single channel of a Y-type micro-channel on a microchip as an aqueous two-phase system. A phase separation multi-phase flow with a liquid-liquid interface was generated due to a phase transformation. An annular flow, one of the flow types in the phase separation multi-phase flow, was observed through bright-field microscopy.

Development of Tube Radial Distribution Chromatography Based on Phase-Separation Multiphase Flow Created via Pressure Loss.

A tube radial distribution chromatography (TRDC) method based on phase-separated multiphase flow created through phase transformation via temperature change has been developed. These systems typically required a temperature-controlling device containing a water bath and a stirrer. Herein, we proposed a novel TRDC system without a cooling device, where the phase transformation was achieved via pressure loss in a capillary tube of 50 μm inner diameter and 550 cm length.

Microfluidic Inverted Flow of Ternary Water/Hydrophilic/Hydrophobic Organic Solvent Solution in a Y-Type Microchannel and a Proposal of the Response Microfluidic Analysis through the Experiment.

Two solutions that are individually fed at the same flow rate into two separate microchannels of a microchip, combine to form a single channel (a Y-type microchannel). This flow is either parallel for immiscible solutions or initially parallel, but then becomes homogeneous through diffusion, for miscible solutions. However, a new type of microfluidic behavior in a Y-type microchannel that was neither parallel nor homogeneous flow has been observed using, for example, water/acetonitrile (3:4.

Ionic Specificity in Rapid Coagulation of Silica Nanoparticles.

The Smoluchowski theory has been widely accepted as the basic theory to estimate the rapid coagulation rate of colloidal particles in electrolyte solutions. However, because the size and specificity of molecules and ions are not taken into account, the theory is applicable only if the particle size is large enough to neglect the effects caused by the structured layers composed of water molecules, ions, and hydrated ions adsorbed on the colloidal surface. In the present study, the rapid coagulation rates of silica nanoparticles in concentrated chloride and potassium solutions were measured by using a low-angle light-scattering apparatus, and the dependence of the experimental value of rapid coagulation rate, K, on the particle diameter, D, and also on the Gibbs free energy of hydration of ions, ΔG, was investigated extensively.

Orders of Magnitude Reduction of Rapid Coagulation Rate with Decreasing Size of Silica Nanoparticles.

The modification of the classical Smoluchowski theory for the rapid coagulation rate of colloidal particles, which takes account of the effect of the squeezing flow between colliding particles, has been widely accepted because it predicts experimental results adequately. However, it is not clear whether the modified theory, in which the coagulation rate is independent of the particle size, is applicable even to nanoparticles in solutions. In the present study, the rapid coagulation rates of silica particles in various 2 M chloride and 1 M potassium solutions were measured by using a low-angle light-scattering apparatus, and the dependence of rapid coagulation rate on the particle diameter, D, was investigated extensively.

Pro-apoptotic protein glyceraldehyde-3-phosphate dehydrogenase promotes the formation of Lewy body-like inclusions.

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has long been recognized as a classical glycolytic protein; however, previous studies by our group and others have demonstrated that GAPDH is a general mediator initiating one or more apoptotic cascades. Our most recent findings have elucidated that an expression of a pro-apoptotic protein GAPDH is critically regulated at the promoter region of the gene. Apoptotic signals for its subsequent aggregate formation and nuclear translocation are controlled by the respective functional domains harboured within its cDNA component.

Disclosure of a pro-apoptotic glyceraldehyde-3-phosphate dehydrogenase promoter: anti-dementia drugs depress its activation in apoptosis.

Overexpression and subsequent nuclear accumulation of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is involved in neuronal apoptosis induced by several stimuli in which GAPDH antisense oligonucleotides specifically block the increment (2 approximately 3 fold) of GAPDH mRNA contents occurring prior to neuronal death. However, these agents do not affect the basal, constitutive mRNA contents. This suggests that there may be distinct gene regulations for GAPDH mRNA expression.

Proapoptotic protein glyceraldehyde-3-phosphate dehydrogenase: a possible site of action of antiapoptotic drugs.

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has long been recognized as a classical glycolytic protein and has been used as a "housekeeping" gene in studies of genetic expression and regulation. However, recent advances reveal that GAPDH displays diverse nonglycolytic functions depending on its subcellular localization. Among those functions, one of the most intriguing is likely to be the induction of apoptosis.