Evaluation of chlorine stabilizing polymer for wound infection control

Introduction: Povidone polymer stabilizes and improves the use of iodine to reduce wound infections, but iodine is a weak oxidizer and not biocompatible.  A halohydantoin-based polymer exists that stabilizes chlorine, and the efficacy for wound infection control of this stronger oxidizing agent which is more biocompatible was assessed.Methods:A halohydantoin-based polymer was assessed against hypochlorous acid for efficacy against five pathogens (a gram positive and gram negative bacteria, and three fungal strains) for minimum inhibitory and minimum biocidal concentrations.  Time kill studies were also performed.  Finally, an ex vivo porcine-based biofilm eradication testing protocols developed and published by iFyber were performed for biofilms grown over 72 hours using P. aeruginosa, S. aureus and Candida albicans as test pathogens using the polymer in solution and hydrogel format. Testing was performed against hypochlorous acid in solution and against commercially available products (triple antibiotic ointment, silver sulfadiazine, clotrimazole) as a hydrogel.Results:The chlorinated polymer performed similar to hypochlorous acid for MIC/MBC testing, was slower to kill pathogens, but performed better in the ex vivo biofilm models. Complete biofilm eradication occurred using 2,000ppm chlorine concentration of the polymer and significant differences (~2 log) were show in performance of the hydrogel compared to commercial products also at 2,000ppm.  Previous experiments showed no skin irritation for the polymer at 6,000ppm in a rabbit model.Discussion: A halohydantoin-based polymer showed similar performance against planktonic pathogens compared to another chlorinated form of biocide and excellent performance in eradicating biofilms in ex vivo porcine skin within the range of acceptable biocompatibility. Further safety data and assessment is warranted, along with in vivo experimentation, given the performance assessed.References:J Antimicrob Chemother 2010; 65: 1712–1719 Wound Management & Prevention 2020;66(11):31–42 doi: 10.25270/wmp.2020.11.3142