Modelling of the temperature gradient across biological cell membranes stressed with pulsed electric fields

Abstract

Membranes of microorganisms stressed with pulsed electric fields (PEF) of sufficient intensity and duration can be permanently damaged by irreversible electroporation. Such PEF-induced damage of a biological cell membrane can lead to the death of the microorganism; this process facilitates practical applications of PEF for microbial inactivation in liquids and lysis. PEF treatment is considered a “non-thermal” inactivation process: typically the global temperature of liquid samples treated with impulsive electric fields remains below the thermal inactivation threshold. However, intense electric fields may result in the development of local temperature gradients across biological membranes. Thus, it is important to investigate these local heating effects for further understanding and optimisation of PEF treatment of microorganisms. Pore formation also happens in biological membranes during PEF treatment, with simulation results showing that local heating also exists in these pores. These heating effects may help enhance the process of the formation of pores during PEF treatment. This local heating in a pore is shown to be influenced by the position and dimension of the pore.