Enhancing Hand Hygiene Compliance through the Long-lasting Antimicrobial Effects of Nitric Oxide-releasing Hand Sanitizer Gel

Abstract

Effective hand hygiene is crucial for reducing the transmission of disease-causing pathogens. While alcohol-based hand sanitizers have become popular, their increased usage during the COVID-19 pandemic raised concerns about their short-lived activity and potential side effects. The increased application of hand sanitizers and harmful side effects has necessitated an effective alternative with prolonged and enhanced antimicrobial properties which could result in a reduced number of sanitizer applications. To address these issues and improve antimicrobial efficacy, this study developed a nitric oxide (NO)-releasing hand sanitizer (NORel) gel enriched with other antimicrobial and moisturizing ingredients like ethanol, tea tree oil, and glycerin. The NORel gel underwent comprehensive analysis, including assessments of pH for 60 d, rheology, NO release, cytocompatibility, and in vitro and ex-vivo antimicrobial effectiveness on rabbit skin proving its ability to eliminate over 97% of bacteria and fungi, including antibiotic-resistant strains. The NORel2 gel demonstrated antimicrobial activity comparable to a commercial alcohol-based gel containing 62% ethyl alcohol, achieving a reduction of more than 5 logs in S. aureus bacteria on a rabbit skin model. Additionally, the NORel gel significantly outperformed the commercial alcohol gel by maintaining its antimicrobial efficacy on infected rabbit skin, showing a persistent activity with a 1.6-log reduction in viable S. aureus 2 h after application. This research introduces a biocompatible NO-releasing gel with superior antimicrobial properties compared to common alcohol-based sanitizers, making it an effective hand hygiene solution to reduce infections, especially in high-risk environments.