Spraying Small Water Droplets Acts as a Bacteriocide.

Maria T Dulay,Ramya Narasimhan,Richard N Zare,Denise M Monack,Jae Kyoo Lee,Alison C Mody

doi:10.1017/qrd.2020.2

Abstract

Disinfectants are important for arresting the spread of pathogens in the environment. Frequently used disinfectants are often incompatible with certain surfaces, expensive and can produce hazardous by-products. We report that micron-sized water droplets can act as an effective disinfectant, which were formed by spraying pure bulk water with coaxial nebulizing airflow. Spraying for 20 min onto Escherichia coli and Salmonella typhimurium on stainless-steel discs caused inactivation of over 98% of the bacteria. Control experiments resulted in less than 10% inactivation (water stream only and gas only) and 55% inactivation with 3% hydrogen peroxide. Experiments have shown that cell death results from cell wall destruction. We suggest that the combined action of reactive oxygen species present in water droplets (but not in bulk water) along with the droplet surface charge is responsible for the observed bactericidal activity.

Highlights

The global market for disinfectants has rapidly grown because of increasing environmental and health concerns and rising global demands for clean food and water
We suggest that the combined action of reactive oxygen species present in water droplets along with the droplet surface charge is responsible for the observed bactericidal activity
We investigated the effectiveness of the AquaROS treatment in killing E. coli and optimized the disinfection power of AquaROS by investigating different parameters of the spray system, including spray distance, gas pressure and water flow rate (Fig. 2)

Summary

Introduction

The global market for disinfectants has rapidly grown because of increasing environmental and health concerns and rising global demands for clean food and water. Chemical disinfectants have had more widespread use with efficiency in destroying the cell walls and disrupting the metabolism of microorganisms (Russell, 2003; Virto et al, 2005; Raffellini et al, 2011). Of these chemical disinfectants, oxidizing agents, such as hypochlorite (bleach), are widely used but have low biodegradability, high cost and are a source of potentially hazardous by-products (McDonnell and Russell, 1999)

Methods

Results

Conclusion