[Use of dielectrophoresis for the preparative separation of thermotolerant yeast cells].

Dielectrophoresis as a new method for preparative separation of cells is being presented. This method responds to differences in the polarization of cells, which correlate with a number of complex physiological properties of cells. It is shown that yeast cells of different thermotolerant properties can be differentiated by dielectrophoresis. Moreover, the application of this method permitted to separate cells with a high selectivity, which produce more biomass at a temperature of 40 degrees C than the initial population. Investigations on the ability of cells to survive in an inhomogeneous a.c. field have shown that the number of dead cells at frequencies of 10(5) cps and 10(6) cps and at field strengths (on the surface of the central electrode) below 2.4 X 10(5) V/m is small. This fact should be considered when picking out suitable separation conditions.