Novel nanosecond pulsed electric field device for noncontact treatment of cells in native culture conditions

Nanosecond pulsed electric fields (nsPEFs) have been found to induce either cell death or cellular changes to a wide range of cells. However, for the current way of delivering the electric field to the cell (by electrodes contacting the cell culture), cells need to be placed in low-conductivity media unsuitable for maintaining cell growth. Here, we present a novel device for noncontact exposure of cells to nsPEF. The cells can be treated in their native cell culture medium and culture vessel. A single-turn loop antenna is designed that can contain a cylindrical cell culture vessel. The electric field within the loop is created by magnetic induction and depends on the time derivative of the current through the loop. To generate the required field strength of 10 kV/cm with duration of ${sim}{rm 6}~{rm ns}$, a fast high-voltage, low-inductance RLC circuit is developed. A fast rising current of 100 A/ns is achieved in this circuit. The developed method is used for the nsPEF treatment of either adherent [Chinese hamster ovary (CHO-K)] or suspension (CHO-S) cells in their native culture medium and vessel. We discovered that nsPEF enhances cell proliferation. This novel effect of nsPEF has significant applicability in improving the yield and lowering the cost of cell cultures and bioreactors.