Microelectronics Technology for Chemo/Biosensors

Summary form only given. The aim in utilizing microfabrication techniques and, in particular, CMOS technology for chemical and biosensors is to devise more intelligent, more integrated, and more reliable sensor systems at potentially low costs in a generic approach. The largely planar integrated circuit (IC) and bio/chemical sensor structures have been extended into the third dimension using microfabrication technologies. Examples of micromachined bio/chemosensors such as cantilevers operated in liquid phase to detect the presence of biomolecules or organic solvents will be shown. Another important trend is the electrical interfacing of CMOS microelectronics with biological entities or electrogenic cells, i.e., cells that react upon electrical stimulation and, in turn, produce electrical signals (heart cells or neurons). Microelectrode arrays (MEAs) are becoming an important tool for non-invasive extracellular recording in the fields of neuroscience and cell-based biosensing. Here, a CMOS-based fully integrated microelectrode array for bidirectional communication (stimulation and recording) with electrogenic cells will be presented, which features on-chip analog and digital signal processing. The device is capable of, e.g., monitoring a relevant electrophysiological response of an in vitro cell or cell culture to an electrical stimulus or a pharmacological agent with prospective applications in the field of bio-inspired information processing or pharmascreening