Downscaling aspects of a conductivity detector for application in on-chip capillary electrophoresis

We are presenting the experimental results of capacitively coupled 2- and 4 -electrode conductivity detector fabricated as a glass dip-stick. These res ults are used as a starting point for investigating the consequences of dow nscaling the device for on-chip capillary electrophoresis (CE) applications , where the detector is located in a separation microchannel. Our studies s how that, it is possible to do accurate and sensitive conductivity sensing in a 150 mum wide channel, by making use of 4-electrode set-up with silicon carbide (SiC) thin insulating layers on top of the electrodes. (C) 2001 El sevier Science B.V. All rights reserved.