Design and Functional Characterization of a Plasma-Activated Aerosol System for Microbial Inactivation

Abstract

This study presents a plasma-activated aerosol (PAA) system for microbial decontamination, combining a corona plasma source with an ultrasonic nebulizer to generate reactive oxygen and nitrogen species (RONS) rich PAA from different liquids. In a 4 L chamber, PAA produced from deionized water achieved a 4.51 ± 0.13 Log reduction of Staphylococcus epidermidis on glass within 10 min. Additional treatments using phosphate-buffered saline solution and a DIW-sodium thiosulfate solution (hydrogen peroxide scavenger) showed reduced antimicrobial efficacy, suggesting a key role for peroxynitrite in bacterial inactivation. A scaled-up 14 L system enhanced treatment uniformity and demonstrated complete inactivation of S. epidermidis, Escherichia coli, and Candida albicans on glass. These findings underscore the efficacy of PAA and its potential in microbial decontamination.