Effect of a Low-conductivity Zone on Field-amplified Sample Stacking in Microchip Micellar Electrokinetic Chromatography

Effect of a low-conductivity zone on field-amplified sample stacking in microchip micellar electrokinetic chromatography.

The effects of a low-conductivity (low-C) zone of an on-line sample preconcentration based on field-amplified sample stacking (FASS) under an acidic condition was investigated in microchip micellar electrokinetic chromatography (MCMEKC). By employing originally fabricated microchips with T- and cross-channel injectors on a single device, partial injection of the low-C zone and large-volume inj...

Development of a Novel On-line Sample Preconcentration and Separation Technique in Microchip Micellar Electrokinetic Chromatography

Fluorescence Imaging Analysis of Transient Trapping–microchip Micellar Electrokinetic Chromatography

This paper reports an fluorescence imaging analysis to verify the proposed mechanisms in transient trapping– microchip micellar electrokinetic chromatography (tr-trapping–MCMEKC). Fluorescence imaging revealed that a process of tr-trapping consisted of four migration stages with different apparent diffusion constants. In the first trapping stage, the diffusion of a focused sample band was suppr...

On-line sample preconcentration using field-amplified stacking injection in microchip capillary electrophoresis.

Previous reports describing sample stacking on microchip capillary electrophoresis (microCE) have regarded the microchip channels as a closed system and treated the bulk flow as in traditional capillary electrophoresis. This work demonstrates that the flows arising from the intersection should be investigated as an open system. It is shown that the pressure-driven flows into or from the branch ...

Nonlinear Effects in Field Amplified Sample Stacking

In field amplified sample stacking (FASS), the sample solution is typically prepared in low conductivity buffer or DI water, so that sample ion concentration can be on the order of the buffer ion concentration. Under these conditions, sample ions can strongly affect conductivity gradients and this leads to nonlinear dispersive effects due to electromigration. We have developed a model to invest...