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bioRxiv · 10.1101/2023.09.20.558698

HOCl-producing Electrochemical Bandages for Treating Pseudomonas aeruginosa-Infected Murine Wounds

Abstract

A novel electrochemical bandage (e-bandage) delivering low-level hypochlorous acid (HOCl) was evaluated against Pseudomonas aeruginosa murine wound biofilms. 5 mm skin wounds were created on the dorsum of Swiss-Webster mice and infected with 106 colony forming units (CFU) of P. aeruginosa. Biofilms were formed over two days, after which e-bandages were placed on the wound beds and covered with Tegaderm. Mice were administered Tegaderm-only (control), non-polarized e-bandage (no HOCl production), or polarized e-bandage (using an HOCl-producing potentiostat), with or without concurrently administered systemic amikacin. Purulence and wound areas were measured before and after treatment. After 48 hours, animals were sacrificed, and wounds were harvested for bacterial quantification. Forty-eight hours of polarized e-bandage treatment resulted in mean biofilm reductions of 1.4 log10 CFUs/g (9.0 vs 7.6 log10; p = 0.0107) vs non-polarized controls, and 2.2 log10 CFU/g (9.8 vs 7.6 log10; p = 0.004) vs Tegaderm only controls. Systemic amikacin improved CFU reduction in Tegaderm-only (p = 0.0045) and non-polarized control groups (p = 0.0312), but not in the polarized group (p = 0.3876). Compared to the Tegaderm only group, there was more purulence reduction in the polarized group (p = 0.009), but not in the non-polarized group (p = 0.064). Wound closure was not impeded or improved by either polarized or non-polarized e-bandage treatment. Concurrent amikacin did not impact wound closure or purulence. In conclusion, an HOCl-producing e-bandage reduced P. aeruginosa in wound biofilms with no impairment in wound healing, representing a promising antibiotic-free approach for addressing wound infections.

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BibTeXRIS

Fleming, D., Bozyel, I., Ozdemir, D., Otero, J. A., Karau, M. J., Anoy, M. M. I., Koscianski, C., Schuetz, A. N., Greenwood-Quiantance, K. E., Mandrekar, J. N., Beyenal, H., Patel, R.. 2023-09-21. HOCl-producing Electrochemical Bandages for Treating Pseudomonas aeruginosa-Infected Murine Wounds. https://doi.org/10.1101/2023.09.20.558698

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