Electrophysiology of Phosphatidylserine Bilayer Membranes Using Electrochemical Impedance Spectroscopy

In this work the electrical properties (resistance and capacitance) of the phospholipid phosphatidylserine, which was recently found to be the major constituent of plasma membranes of cancer cells that undergo chemotherapy, were measured using electrochemical impedance spectroscopy (EIS) in the frequency range 0.01 Hz to 100 kHz. The measurements show that the resistance of phosphatidylserine is 800 kω and the capacitance is approximately 90 pF. These numbers are significantly less than the reported resistance and capacitance of a lipid bilayer membrane that is composed primarily of phosphatidylethanolamine, which is the major constituent in plasma membranes in normal cells. Consequently, the results show that the electrical conductivity of the membranes of cancer cells increase significantly following chemotherapy treatments.