Microfabrication of chemical sensors and biosensors for environmental monitoring

Various microfabrication techniques have been employed for the development of microchemical sensors and biosensors. In view of the environmental applications, the techniques are useful in the development of inexpensive disposable sensors. An example is the miniature Clark-type oxygen electrode, which is a basic element for microorganism-based biosensors for Biochemical Oxygen Demand (BOD) or toxicity for high-risk compounds. The microfabrication technology provides versatility. Other than amperometric and potentiomentric sensing, various sophisticated electrochemical techniques could be performed using an on-chip electrochemical cell. This will be an aid for the field-analysis of heavy metal ions. The microfabrication technology also enables multi-analyte detection and realization of the Micro Total Analysis System (mu TAS), which will improve the throughput of the field-analyses. (C) 2000 Elsevier Science S.A. All rights reserved.