CAPILLARY ELECTROPHORESIS CHIPS WITH INTEGRATED ELECTROCHEMICAL DETECTION

Capillary electrophoresis systems with integrated electrochemical dete ction have been microfabricated on glass substrates. Photolithographic placement of the working electrode just outside the exit of the elect rophoresis channel provides high-sensitivity electrochemical detection with minimal interference from the separation electric field. Microch ip electrophoretic separations of neurotransmitters in under 100 exemp lify the good resolution and attomole detection sensitivity of these d evices. Using indirect electrochemical detection, high-sensitivity DNA restriction fragment and PCR product sizing has also been performed. These microdevices match the detector's size to that of microfabricate d separation and reaction devices, bringing to reality the lab-on-a-ch ip concept.