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, 50 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 silicon wafer. The reactor structure occupied a silicon wafer area of 3 mm X 15 mm and had a total volume of 4.2 mul. Peroxidase (POD) and glucose 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 measurements showing a dynamic response to glucose concentrations ranging from 0 to 34 mM.