A μTAS Based on Microdialysis for On-Line Monitoring of Clinically Relevant Substances

Abstract

For the monitoring of various clinically relevant substances such as glucose, lactate and electrolytes a μTA8 based on microdialysis is under development. Two modules needed in this analysis system will be presented. One component of the system is an integrated microdialysis probe that is connected with an extremely low dead volume to a channel system in silicon. This small dead volume is an important requirement for microdialysis based measurement systems because flow rates are as low as 0.2–2 μl/min. A part of the integrated channel system is in contact with an array of cavities having internal metal electrodes. These cavities can be filled with for instance an ion selective filling or a hydrogel containing enzyme contacting the dialysate stream via a liquid-liquid junction. The resulting ion-selective or enzymatic micro sensors can be applied for on-line analysis of the sample stream coming from the microdialysis probe.