Patent ID: 6169394
Filing Date: 2001-01-02
Classification: G01N

Abstract:
A method for monitoring a test sample in a micro-analysis system, comprising the steps of: providing a micro-electric sensor device in a micro-analysis system, the micro-electric sensor device comprising: a substrate having a substantially planar upper surface; at least one microchannel formed in the upper surface of the substrate and defined by a pair of opposing sidewalls and a bottom wall in the substrate; one or more reservoirs formed in the planar surface of the substrate and in fluid communication with the microchannel; and at least one pair of opposing electrodes on the planar surface of the substrate and terminating at electrode tips formed on the opposing sidewalls of the microchannel such that the electrode tips face each other, thereby creating a detection zone in the microchannel between and adjacent to the electrodes; supplying electrical power to the electrodes to create an electric field in the detection zone of the microchannel; injecting a test sample into the microchannel; and detecting changes in the electric field as the test sample enters the detection zone of the microchannel to provide conductivity or impedance based measurements of the test sample in the microchannel.