Distributed compact plasma reactor decontamination for planetary protection in space missions

Abstract

This paper presents a proof-of-concept study establishing effectiveness of the Active Plasma Sterilizer (APS) for decontamination in planetary protection. The APS uses Compact Portable Plasma Reactors (CPPRs) to produce surface dielectric barrier discharge, a type of cold plasma, using ambient air to generate and distribute reactive species like ozone used for decontamination. Decontamination tests were performed with pathogenic bacteria (Escherichia coli and Bacillus subtilis) on materials (Aluminum, Polycarbonate, Kevlar and Orthofabric) relevant to space missions. Results show that the APS can achieve 4 to 5 log reductions of pathogenic bacteria on four selected materials, simultaneously at 11 points within 30 min, using power of 13.2 ± 2.22 W. Spatial decontamination data shows the APS can uniformly sterilize several areas of a contaminated surface within 30 min. Ozone penetration through Kevlar and Orthofabric layers was achieved using the CPPR with no external agent assisting penetration. Preliminary material compatibility tests with SEM analysis of the APS exposed materials showed no significant material damage. Thus, this study shows the potential of the APS as a light-weight sustainable decontamination technology for planetary protection with advantages of uniform spatial decontamination, low processing temperatures, low exposure times, material compatibility and the ability to disinfect porous surfaces.

Inactivation of SARS CoV-2 on porous and nonporous surfaces by compact portable plasma reactor

“…The CPPR is based on cold plasma generated ozone, an alternative decontamination technology, that works under ambient conditions. Previous studies on CPPR have shown its effectiveness against various types of bacteria ( Choudhury et al, 2018 ; Roy et al, 2021 ; Choudhury et al, 2023 ). The SARS-COV-2 inactivation results presented in this paper, along with previously published literature on CPPR and ozone ( Kogelschatz, 2003 ; Park et al, 2006 ; Choudhury et al, 2018 ; Roy et al, 2021 ; Choudhury et al, 2023 ), establishes the potential of CPPR as a decontamination technology for preventing HAIs (hospital acquired infections), further spread of COVID-19 and possible future outbreaks.…”

“…Previous studies have established the effectiveness of CPPR against bacterial and fungal species including Escherichia coli , Bacillus subtilis , Pseudomonas aeruginosa , Enterobacter sp., Chrysobacter sp., Aspergillus sp., Xanthomonas sp., Chromobacter sp., Fusarium sp. and Enterobacter sp., and Staphylococcus aureus ( Choudhury et al, 2018 ; Roy et al, 2021 ; Choudhury et al, 2023 ).…”

Sterilization characteristics of narrow tubing by nitrogen oxides generated in atmospheric pressure air plasma

“…Residual toxic and/or carcinogenic chemicals may endanger patients, sterilization operators, and medical professionals. Recently, plasma sterilization methods have been studied owing to potential for low toxicity and reduced sterilization times 2 – 6 . Although many plasma sterilization methods been applied to plastic tubing, effective sterilization methods have yet to be developed because of heat and damage caused to the tubing material 7 – 10 .…”

Ozone Generation by Surface Dielectric Barrier Discharge

“…They found that the nitrogen oxides generated in the discharge were the main species contributing to the sterilization process. Portugal et al [16] and Choudhury et al [17,18] studied the ozone flow generated by the fan-shaped SDBD reactor. They found that the fan-shaped electrode improves ozone distribution and the decontamination process compared to the traditional comb-shaped design.…”