PLANAR CHIP TECHNOLOGY FOR CAPILLARY ELECTROPHORESIS

Miniaturization of separation columns implies equally reduced volumes of injectors, detectors and the connecting channels. Planar chip technology provides a powerful means for the fabrication of micron sized structures such as channels. This is demonstrated with three examples. An optical absorbance detector chip exhibits the expected behavior of a 1 mm optical pathlength cell despite its volume of 4 nL. A capillary electrophoresis device allows for integrated injections of 100 pL samples, for efficiencies of 70000 to 160000 theoretical plates in 10 to 20 seconds, and for external laser-induced fluorescence detection at any capillary length of choice between 5 and 50 mm. A system for synchronized cyclic capillary electrophoresis is also presented in which plate numbers per volt can be dramatically increased.