Shah convolution differentiation Fourier transform for rear analysis in microchip capillary electrophoresis

This paper first reports the application of Shah convolution differentiatio n Fourier transform for rear analysis. Rear analysis eliminates the need to create a well-defined and reproducible sample plug, thus making the operat ion simpler. The number of solution reservoirs, for microchip capillary ele ctrophoresis (CE), could be reduced from the usual four to three. Sample bi as in CE could be avoided too. The separation channel was first filled with the fluorescent sample solution, and subsequently flushed out with the buf fer. The rear of each analyte zone gives rise to its flight of sigmoid-shap ed steps in the time-domain. The time-domain detector signal was first diff erentiated and then Fourier transform was performed. The Fourier transform results were represented in the form of a magnitude plot. It is proposed th at this would be as equally applicable to other separation techniques (e.g. , chromatography) and detection methods (e.g., absorption). (C) 2001 Elsevi er Science BV All rights reserved.