Fabrication of amperometric sensor-based microsystems for biomedical applications

This work reports the design and fabrication of an amperometric three-electrode silicon sensor packaged in a hypodermic needle for monitoring physiological chemical parameters. The sensor consists of two platinum electrodes, respectively the working electrode and the counter electrode, and an Ag/AgCl electrode as reference. The microsystem is suitable for metabolites detection if enzymes are deposited on the working electrode. Different electrodes configurations have been fabricated by using silicon micromachining techniques. Characterisation has been performed with particualar attention to investigate reference electrode properties