Monitoring of biological cell collection by dielectric spectroscopy

Impedance spectroscopy of cells or other microparticles collected on electrode arrays, by simultaneous dielectrophoresis is described. Real-time measurements are possible because the RF voltage used to drive dielectrophoresis is nulled at the impedance instrument. The arrangement can be used to quantify the extent of dielectrophoretic collection and hence as a detector for the presence of highly polarizable particles. The impedance spectra of dielectrophoretic collections of two different species of yeast cells were monitored. Both control and permeabilized cells were measured. The data indicate the possibility of single-cell sensitivity with this technique