We introduce powder blasting for the fabrication of glass microchips. Powder blasting is a fast and cheap technique with which we pattern channels in sodalime and pyrex glass with a width down to 100 mm. We combine the technique with appropriate bonding procedures to realise sealed microchannel structures. We study the transport of¯uorescent dye solutions and¯uorescent beads within channels made by powder blasting and in`classical' channels made by HF-etching. We ®nd a remarkable difference in sign of the electric ®eld induced¯ow for both types of channels and explain the observed strong plug broadening effects in the powder blasted channels. #
New chiral stationary phases derived from enantiomerically pure derivatives of cysteine carrying sulfonic acid groups are synthesized and evaluated for enantiomer separation of chiral bases by non aqueous capillary electrochromatography after bonding to a linker and grafting upon thiol-modified silica particles. Structural modifications of these low molecular weight chiral selectors are investigated and discussed in terms of apparent enantioselectivities and resolution factors based on the enantiomeric separations of a set of chiral bases including beta-blockers, beta-sympathomimetics and other basic drugs. The influence of the mobile phase constitution and its flow velocity on the enantioseparation by nonaqueous capillary electrochromatography is also briefly evaluated and discussed for the chiral substances investigated.
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