Pulsed Power for Wound Healing

A new method for stimulating platelet aggregation that does not rely on thrombin is based on the effect of ultrashort (nanosecond) pulsed electric fields. Nanosecond pulsed electric fields stimulate a variety of physiological responses, among them, Ca²⁺ fluxes, which in turn lead to platelet activation. We have shown that when platelet rich plasma was pulsed with one 300 ns pulse at 30 kV/cm, platelets aggregated and a platelet gel was produced. In addition, platelet derived growth factor (PDGF) release from platelets was observed. Since platelet aggregation occurs just minutes after pulsing, the pulse generator, the platelet gel reactor and the gel delivery system need to be integrated into one, easy-to-use system. Another consideration is the volume of activated platelet gel required for a treatment. This requires a batch mode platelet exposure system where relatively large quantities of platelet gel can be treated in less than three minutes. We have built a compact, easy to use, pulsed power generator with a Blumlein line pulse-forming network that generates pulses of 300 ns duration. The impedance of the Blumlein line is 10 Omega, matching the resistance of the exposure cell, a custom-made 6-mm chamber, which contains 5.4 ml of the platelet rich plasma. The output voltage can be varied, up to 20 kV, allowing the generation of electric fields of up to 30 kV/cm in the chamber. In order to minimize the time required for activation of the 70 ml of platelet gel, we operate the system in a batch mode.