Antimicrobial Efficacy and Safety of a Novel Gas Plasma-Activated Catheter Lock Solution

Bhatt, S.; Mehta, P.; Chen, C.; Daines, D. A.; Mermel, L.; Chen, H.; Kong, M.

doi:10.1101/302919

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bioRxiv · 10.1101/302919

Antimicrobial Efficacy and Safety of a Novel Gas Plasma-Activated Catheter Lock Solution

Bhatt, S.·Mehta, P.·Chen, C.·Daines, D. A.·Mermel, L.·Chen, H.·Kong, M.

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Abstract

Antimicrobial lock solutions are important for prevention of microbial colonization and infection of long-term central venous catheters. We investigated the efficacy and safety of a novel antibiotic-free lock solution formed from gas plasma-activated disinfectant (PAD). Using a luminal biofilm model, viable cells of methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Candida albicans in mature biofilms were reduced by 6 - 8 orders of magnitude with a PAD lock for 60 minutes. Subsequent 24-hour incubation of PAD-treated samples resulted in no detectable regrowth of viable bacteria or fungi. As a comparison, the use of a minocycline/EDTA/ethanol lock solution for 60 minutes led to regrowth of bacteria and fungi, up to 107 - 109 CFU/ml, in 24 hours. The PAD lock solution had minimal impact on human umbilical vein endothelial cell viability, whereas the minocycline/EDTA/ethanol solution elicited cell death in nearly half of human endothelial cells. Additionally, PAD treatment caused little topological change to catheter materials. In conclusion, PAD represents a novel antibiotic-free, non-cytotoxic lock solution that elicits rapid and broad-spectrum eradication of biofilm-laden microbes and which shows promise for the prevention and treatment of intravascular catheter infections.

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Bhatt, S., Mehta, P., Chen, C., Daines, D. A., Mermel, L., Chen, H., Kong, M.. 2018-04-17. Antimicrobial Efficacy and Safety of a Novel Gas Plasma-Activated Catheter Lock Solution. https://doi.org/10.1101/302919

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