Killing Bacteria Using Acetic Acid and Nanosecond Pulsed Electric Fields—An In Vivo Superficial Infection Model Study and Immune Response

Abstract

Invasive infections caused by drug-resistant bacteria are a problem responsible for many fatal cases, especially in burn wound care centers, while bacterial resistance to antibiotics is growing dramatically worldwide. In this work, we utilize pulsed electric fields (up to 25 kV/cm × 750 ns) in combination with low-concentration (1%) acetic acid for the inactivation of P. aeruginosa. An in vivo superficial infection model is developed in BALB/C mice using a luminescent strain of P. aeruginosa. We show that an up to 25 kV/cm electric field (3 kV, 1.2 mm gap), when combined with acetic acid, induces a bacteriostatic effect, preventing further infection for up to 7 days after treatment. Additionally, we evaluate antibodies against surface and intracellular P. aeruginosa bacteria antigens following the treatment. It is shown that the levels of surface IgG and IgG1 antibodies are significantly lower in the murine serum of electric-field-treated mice compared to the bacterial-infection-bearing group of mice treated with acetic acid alone. The results of this work are useful as a proof of concept for the development of novel clinical procedures to fight drug-resistive microorganisms responsible for wound contamination and chronic wounds.