A single cell multi-analysis system for electrophysiological studies

Abstract

A micro analysis system for multi-purpose electrophysiological studies of single cells has been designed, fabricated, and characterized. The micro electrophysiological analysis system (/spl mu/-EPAS) contains multiple extracellular opposing electrode pairs that interface with a single cell inside an analysis cavity. These electrodes can be used for general single electrode extracellular stimulation/recording studies, dual electrode applications such as impedance spectroscopy, and for applications requiring a greater number of electrodes such as impedance tomography. Additionally, the analysis system contains a sealing/clamping mechanism and a backside extracellular reference electrode for patch clamping studies. The analysis cavities were designed in an array format for parallel analyses. Bovine chromaffin cells were used as a target to demonstrate and characterize the system. Using the integrated glass sealing ring, giga-seals were obtained on a population of chromaffin cells. The micro system generated maximum giga-seal resistances of 1.2G/spl Omega/ with non-sealed average cavity-to-backside resistances of 0.5M/spl Omega/. Furthermore, the cellular analysis system was demonstrated for electrical impedance spectroscopy on chromaffin cells over a range from 40.0 Hz to 1.0 MHz.