Richard J. McReynolds

Micromachined Flow-Through Measurement Chambers Using LAPS Chemical Sensors

Micro Total Analysis Systems (µTAS) are envisioned as small analytical systems with incorporated sample handling. We discuss the concept of a system consisting of a microflow chamber in which a biological component is immobilized, and a chemical sensor which is part of the chamber. A particularly suitable sensor is the Light-Addressable Potentiometric Sensor (LAPS), due to its compatibility with micromachined surfaces and structures. Flow chambers are made by anisotropically etching channels in silicon, at the bottom of which one or more LAPS devices are defined. Eight separate flow channels are present on a 23 mm square chip. Data is presented on two types of biological components: enzymes and living cells.