Miniaturisierte elektrochemische Detektoren für kapillare Analysesysteme

The following results consist of three stages of development. The first stage starts with an introduction to the field of copper microdisc electrodes and the evolution of an exemplary analysis method for the amperometric detection on such electrodes. Building upon the results gained in the first stage it is possible to fabricate metallic thin layer electrodes in the second stage with the aid of microsystem technology. Also their electrochemical characterization is realized. Besides thin layer electrodes made of gold and platinum such electrodes made of copper are introduced for the first time. Further more the analytical use of thin layer electrodes as discrete electrochemical detectors in capillary electrophoresis is presented. In this context two detector layouts are compared. In addition to the classic wall jet detector using planar microelectrodes a new "tangentially approached" detector is closely studied in this work. The last stage of development deals with the production of microchannels made of polymeric materials. New is the integration of thin layer electrodes for the high voltage as well as for the electrochemical detection. The combination of microchannels with thin layer electrodes results in a working CE-chip with electrochemical detection.