Inactivation of microorganisms within collagen gel biomatrices using pulsed electric field treatment

Pulsed electric field (PEF) treatment was examined as a potential decontamination method for tissue engineering biomatrices by determining the susceptibility of a range of microorganisms whilst within a collagen gel. High intensity pulsed electric fields were applied to collagen gel biomatrices containing either Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis, Candida albicans, Saccharomyces cerevisiae or the spores of Aspergillus niger. The results established varying degrees of microbial PEF susceptibility. When high initial cell densities (10⁶–10⁷ CFU ml⁻¹) were PEF treated with 100 pulses at 45 kV cm⁻¹, the greatest log reduction was achieved with S. cerevisiae (~6.5 log₁₀ CFU ml⁻¹) and the lowest reduction achieved with S. epidermidis (~0.5 log₁₀ CFU ml⁻¹). The results demonstrate that inactivation is influenced by the intrinsic properties of the microorganism treated. Further investigations are required to optimise the microbial inactivation kinetics associated with PEF treatment of collagen gel biomatrices.