A low power flexible dielectric barrier discharge disinfects surfaces and improves the action of hydrogen peroxide.

ABSTRACT: There is an urgent need for disinfection and sterilization devices accessible to the public that can be fulfilled by innovative strategies for using cold atmospheric pressure plasmas. Here, we demonstrate a successful novel combination of a flexible printed circuit design of a dielectric barrier discharge (flex-DBD) with an environmentally safe chemical reagent for surface decontamination from bacterial contaminants. Flex-DBD operates in ambient air, atmospheric pressure, and room temperature without any additional gas flow at a power density not exceeding 0.5 W/cm². The flex-DBD activation of a 3% hydrogen peroxide solution results in the reduction in the bacterial load of a surface contaminant of?>?6log₁₀ in 90 s, about 3log₁₀ and 2log₁₀ better than hydrogen peroxide alone or the flex-DBD alone, respectively, for the same treatment time. We propose that the synergy between plasma and hydrogen peroxide is based on the combined action of plasma-generated OH^· radicals in the hydrogen peroxide solution and the reactive nitrogen species supplied by the plasma effluent. A scavenger method verified a significant increase in OH^· concentration due to plasma treatment. Novel in-situ FTIR absorption spectra show the presence of O₃, NO₂, N₂O, and other nitrogen species. Ozone dissolving in the H₂O₂ solution can effectively generate OH^· through a peroxone process. The addition of the reactive nitrogen species increases the disinfection efficiency of the hydroxyl radicals and other oxygen species. Hence, plasma activation of a low concentration hydrogen peroxide solution, using a hand-held flexible DBD device results in a dramatic improvement in disinfection.

SUBMITTER: Gershman S 

PROVIDER: S-EPMC7907379 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature