# Biological Decontamination by Microplasma
## 5 Conclusions  
The biological decontamination of _Escherichia coli_, _Pseudomonas aeruginosa_, and _Staphylococcus aureus_ was carried out by microplasma energized at \(-\)1.5 kV and \(-\)1.7 kV negative-pulse voltage. Inhibition zones with 100% inhibition efficiency at least 45 mm in diameter were measured on the agar plates for all bacterial strains after microplasma treatment at \(-\)1.7 kV discharge voltage. The inhibition efficiency increased with the increase in discharge voltage. The calculated D values, considering the inhibition zones below the electrode, were 5.4 kJ/mL at \(-\)1.7 kV for _E. coli_. Although, the CFU cannot be calculated or estimated in the case of _P. aeruginosa_ due to the dense bacterial populations, the inhibition zone with 100% efficiency was clear. This demonstrates the effect of microplasma on Gram-negative bacteria such as _E. coli_ and _P. aeruginosa_. For _S. aureus_, which is a Gram-positive bacteria, the effect of microplasma was also clear, with a calculated D value of 19.9 kJ/mL at \(-\)1.5 kV discharge voltage. No inhibition was observed after the microplasma treatment of already-grown bacteria, indicating that the system is more suited as a prophylactic measure, rather than a complete decontamination of a surface. The process of bacteria inactivation is due to the action of ROS and RON. The results obtained recommend microplasma as a safer and more economical alternative to classical sterilization technologies and also other plasma technologies, due the low discharge voltage and reduced size that furthermore can translate to the portability of the microplasma system. M.G.B. Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Software, Supervision, Validation, Visualization, Writing--original draft, review and editing. A.C.: Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Software, Supervision, Validation, Visualization, Writing--original draft, review and editing. E.S. : Conceptualization, Funding acquisition, Resources, Validation. V.S. : Data curation, Formal analysis, Investigation. K.S. : Conceptualization, Investigation, Validation. All authors have read and agreed to the published version of the manuscript. This research was funded by the \"Nucleu\" Program within the National Plan for Research, Development and Innovation 2022-2027, project PN 23 24 02 01. Not applicable. [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Comparison of inactivation characteristics of _Escherichia coli_ and _Staphylococcus aureus_ in water by rotary plasma jet sterilization. _Environ. Technol. Innovc._**2024**, _36_, 103746. [CrossRef]
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