Efficacy of a New Alcohol-Free Organic Acid-Based Hand Sanitizer against Foodborne Pathogens

Gözde Bayer; Amirreza Shayganpour; Ilker S Bayer

doi:10.3390/toxics11110938

Efficacy of a New Alcohol-Free Organic Acid-Based Hand Sanitizer against Foodborne Pathogens

Toxics. 2023 Nov 17;11(11):938. doi: 10.3390/toxics11110938.

Authors

Gözde Bayer¹, Amirreza Shayganpour², Ilker S Bayer²

Affiliations

¹ DS Bio ve Nanoteknoloji A. Ş, Lavida City Plaza 45/7, 06530 Ankara, Türkiye.
² Smart Materials, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.

Abstract

In light of the global health crisis triggered by the COVID-19 pandemic, numerous experts have deemed the utilization of hand sanitizers imperative as a precautionary measure against the virus. Consequently, the demand for hand sanitizers has experienced a substantial surge. Since the beginning of 2020, the utilization of alcohol-free hand sanitizers has been increasingly favored due to the potential risks associated with alcohol poisoning, flammability, as well as the adverse effects on skin lipid dissolution, dehydration, and sebum reduction, which can lead to severe cases of eczema and norovirus infections. In this study, we developed an aqueous hand sanitizer that does not contain alcohol. The sanitizer consists of naturally occurring, food-grade organic acids, including lactic, citric, and azelaic acids. Additionally, food-grade ammonium sulfate and a small amount of povidone-iodine (PVPI) were included in the formulation to create a synergistic and potent antibacterial effect. The effectiveness of the hand sanitizer was evaluated against four common foodborne pathogens, namely Clostridium botulinum, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus, via in vitro testing. The organic acids exhibited a synergistic inhibitory function, resulting in a 3-log reduction in CFU/mL. Furthermore, the presence of povidone-iodine and ammonium sulfate enhanced their antibacterial effect, leading to a 4-log reduction in CFU/mL. The hand sanitizer solution remained stable even after 60 days of storage. During this period, the detection of additional triiodide (I₃^-) ions occurred, which have the ability to release broad-spectrum molecular iodine upon penetrating the cell walls. This alcohol-free hand sanitizer may offer extended protection and is anticipated to be gentle on the skin. This is attributed to the presence of citric and lactic acids, which possess cosmetic properties that soften and smoothen the skin, along with antioxidant properties.

Keywords: azelaic acid; citric acid; foodborne pathogen; hand sanitizer; lactic acid; povidone-iodine.

Grants and funding

The authors acknowledge financial support and use of laboratory facilities from DS Bio ve Nanoteknoloji Inc., Ankara, Türkiye, and Hacettepe University Applied Technologies Application and Research Center (HUNITEK) Ankara, Türkiye for microscopy support and analysis.