Title: Synergistic augmentation of EtOH and 4-Watt ultraviolet-C for rapid surface decontamination

Authors: Jahanzeb Sheikh; Tan Tian Swee; Syafiqah Saidin; Chua Lee Suan; Sameen Ahmed Malik

Addresses: Department of Biomedical Engineering and Health Sciences, Faculty of Electrical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Malaysia; Department of Biomedical Engineering, Sir Syed University of Engineering and Technology, Pakistan ' Department of Biomedical Engineering and Health Sciences, Faculty of Electrical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Malaysia; IJN-UTM Cardiovascular Engineering Centre, Institute of Human Centered Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor, Malaysia ' Department of Biomedical Engineering and Health Sciences, Faculty of Electrical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Malaysia; IJN-UTM Cardiovascular Engineering Centre, Institute of Human Centered Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor, Malaysia ' Institute of Bioproduct Development, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor Bahru, Johor, Malaysia ' Department of Bio-medical Engineering, Faculty of Electrical Engineering, University of Engineering and Technology Lahore – Narowal Campus, Narowal, 51600, Punjab, Pakistan

Abstract: Bacterial contamination poses significant health risks, especially in densely populated settings like educational institutions. This study in a Malaysian educational institute examined bacterial deposition on frequently touched surfaces and evaluated the efficacy of 70% ethanol (EtOH) with 10-s of contact time, combined with ultraviolet (UV) light irradiation under varied time exposures durations. Results showed that EtOH-only treatment was least effective on lift-2, with a 20% inactivation rate, while other surfaces revealed efficiencies between 69.19% and 84.4%. However, employment of EtOH-UV treatment achieved highest inactivation across all the samples treated within 60-s requiring 0.15 mJ/cm₂ of dose. However, swab obtained from lift-1 could sustain 1.41-log₁₀ inactivation under maximum exposure settings. Scanning electron microscopy (SEM) further validated the persistence of Bacillus spp, Staphylococcus spp, and E. coli colonies. This study underscores the need for comprehensive disinfection strategies in educational facilities to reduce bacterial contamination, highlighting the enhanced efficacy of the combined EtOH-UV treatment.

Keywords: bacteria; decontamination; disinfectants; ethanol; EtOH; environment; high-touch surface; low-touch surface; pathogens; ultraviolet-C.

DOI: 10.1504/IJBET.2025.143743

International Journal of Biomedical Engineering and Technology, 2025 Vol.47 No.1, pp.28 - 43

Received: 25 Jun 2024
Accepted: 14 Jul 2024
Published online: 06 Jan 2025 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article