A bio-analytical system for rapid cellular electrophysiological assays

In this paper, the use of non-uniform ac electric fields on biological cells for bioanalysis, through multiple, independently configurable channels is presented. The programmable system has been used to obtain the dielectrophoretic spectra of cells in near real time, within 90 seconds. This is a significant improvement on existing dielectrophoretic techniques as simultaneous parallel measurement of the dielectrophoretic forces at different frequencies has potential of revealing subtle changes to the electrophysiology of cells, as they occur. The results show that with continuous on-chip monitoring, cells exposed to a chemical agent that induces apoptosis begin to exhibit a spectrum that differs from untreated cells, as indicated from shifts in the observed crossover frequency values.