Improving resolution in capillary zone electrophoresis through bulk flow control

One can increase the residence time of analytes in a capillary electrophore sis experiment by reducing the electroosmotic flow. Such measures increase separation efficiency and resolution. It is posible to accomplish this by h ydrostatic backflow but dispersion induced by the parabolic flow profile ca uses considerable plate losses except with extremely small diameter capilla ries. Relative to hydrostatic backflow, auxiliary electroosmotic pumping, d eployed to increase residence time, produces better resolution at the same residence time and thus constitutes a superior alternative, (C) 1999 Academ ic Press.