Combination of 70% ethanol and 2% potassium aluminum sulfate as a modified antibacterial disinfectant

Abstract

Background: Mobile phones used by health-care workers can harbor pathogenic bacteria. Effective techniques are therefore needed to prevent bacterial transmission through mobile phones, including the development of new or modified disinfectants. Methods: In total, 100 swabs were collected from the mobile phones of health-care workers. All samples were directly cultured and incubated for 24 h at 37°C. The samples were divided into two groups (n = 50 each): one disinfected with 70% ethanol alone and the other with 70% ethanol containing 2% potassium aluminum sulfate (alum). Results: Bacterial growth before disinfection with 70% ethanol alone was observed in 92% of samples, which decreased to 66% after disinfection. With 70% ethanol plus 2% alum, bacterial growth before disinfection was 88%, decreasing to 16% after disinfection. The mean number of colonies before disinfection with 70% ethanol alone was 22.80 ± 10.38, while after disinfection, it was 3.48 ± 1.40 (P < 0.00001). Similarly, the number of colonies before disinfection with 70% ethanol plus 2% alum was 19.84 ± 9.34, while that after disinfection was 0.68 ± 0.33 (P < 0.00001). Conclusion: To the best of our knowledge, this is the first study to evaluate the combination of 70% ethanol with 2% alum to enhance the antimicrobial efficacy of ethanol as a new modified disinfectant.