Application of the Electrical Sizing Principle of Coulter to a New Multiparameter System

A new technique is described for simultaneously measuring, within 100 ¿s, cell volume, membrane breakdown voltage, and internal conductivity on individual cells of microscopic dimensions. The system is a modification of the hydrodynamically focusing Coulter Counter®. Tumor cells established from rat fetal brain cells of average volume 2100 ¿m3 were measured. A breakdown voltage of 0.86 V was found with an apparent volume underestimation after breakdown of 40 percent.