CONTINUOUS ELECTROPHORETIC SEPARATIONS IN NARROW CHANNELS COUPLED TO SMALL-BORE CAPILLARIES

Continuous zone electrophoretic separations in channels have been demo nstrated. This new technique has the potential to continuously sample and separate analytes from volume-limited microenvironments. A small-b ore capillary is used to electrophoretically sample, but not separate, a mixture of dansylated amino acids. The capillary is coupled to a qu artz channel structure in a manner which allows continuous injection o f the sampled material into the channel. The channel functions to cont inuously separate the sampled material via electrophoresis. A laser-in duced fluorescence detection scheme, which involves two fiber optic ar rays situated at the channel exit, monitors eluting analytes. A contin uous separation of dansylated amino acids on the time scale of a few m inutes demonstrates the utility of the technique. Sampling has been pe rformed continuously up to 400 s, and initial detection limits are app roximately 30 muM.