posted on 2008-07-10, 11:51authored byStefano Perni, Gilbert Shama, J.L. Hobman, P.A. Lund, C.J. Kershaw, G.A. Hidalgo-Arroyo, C.W. Penn, Xu-Tao Deng, James L. Walsh, Michael G. Kong
Mechanisms of plasma induced microbial inactivation have commonly been studied with physico-chemical techniques. In this letter, Escherichia coli K-12 and its ∆recA, ∆rpoS and ∆soxS mutants are employed to discriminate effects of UV photons, OH radicals, and reactive oxygen species produced in atmospheric discharges. This microbiological approach exploits the fact that these E. coli mutants are defective in their resistance against various external stresses. By interplaying bacterial inactivation kinetics with optical emission spectroscopy, oxygen atoms are identified as a major contributor in plasma inactivation with minor contribution from UV photons, OH radicals, singlet oxygen metastables, and nitric oxide.
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School
Mechanical, Electrical and Manufacturing Engineering
Citation
PERNI, S. ... et al, 2007. Probing bactericidal mechanisms induced by cold atmospheric plasmas with Escherichia coli mutants. Applied Physics Letters, 90 (7), article 073902