A MICROMACHINED ENZYME REACTOR IN (110)-ORIENTED SILICON

An enzyme reactor was fabricated in a [110]-oriented silicon wafer. By using anisotropic etching a structure with 30 channels, 12 mm long, 5 0 mum wide and spaced 50 mum apart was achieved. The channel formation was sealed by anodic bonding of a glass lid to the surface of the sil icon wafer. The reactor structure occupied a silicon wafer area of 3 m m X 15 mm and had a total volume of 4.2 mul. Peroxidase (POD) and gluc ose oxidase (GOD) were immobilized on two different reactor structures . The amount of active enzyme in the POD reactor was estimated to 4.8- mU. The GOD reactor was connected to a system for continuous glucose m easurements showing a dynamic response to glucose concentrations rangi ng from 0 to 34 mM.