Table 1.

Mechanisms of Virus Inactivation by Plasma^a

Virus	ROS/RNS involved in inactivationb	Mode of virus inactivation		Methods for identification of virus inactivation		Methods used for CP characterizationc	Refs
		Protein degradation	DNA/RNA degradation	Protein degradation	DNA/RNA degradation
Bacteriophages
λ	NA	Yes	Yes	SDS-PAGE alone or in combination with in vitro packaging	Agarose gel electrophoresis alone or in combination with in vitro packaging	Optical emission spectroscopy	[50]
MS2d	↑O	Yes	Yes	SDS-PAGE	RT-PCR, agarose gel electrophoresis	Optical emission spectroscopy	[49]
MS2	O3e	NA	No	Not measured	RT-qPCR	Ozone sensor	[41]
T4	1O2f	Yes	Yes	SDS-PAGE	Agarose gel electrophoresis	H2O2/peroxidase assay kit, nitrite/nitrate colorimetric assay kit, electron spin resonance	[46]
Animal surrogates of enteric viruses
FCVg	1O2 or ONOOH (in acidic conditions)f, O3h, H2O2, NO2−e.	Yes	NA	SDS-PAGE, LC-MS/MS	Not measured	Colorimetric assay with titanium sulfate, Griess assay, LC/MS equipped with an electrospray ionization ion source, fluorescence probe, spectrophotometry	[22]
FCV	1O2 and ONOO− or ONOOH (acidic conditions)f	NA	Yes	Not measured	RT-qPCR	Optical emission spectroscopy, UV test strips, Griess assay, H2O2 test strips	[28]
FCV	1O2f, O3h	Yes	Yes	EMA-RT-qPCR, EMA-RT-PCR, SDS-PAGE	RT-PCR, RT-qPCR, sequencing	Indirect measurements with LC-MS/MS	[21]
FCV	NOx, O3f	NA	NA	Not measured	Not measured	UV light meter, UV absorption spectroscopy, Griess assay	[20]
Human viruses
Adenovirus	H2O2e	No	Yes	Immunochromatography and Western blotting	PCR, qPCR	H2O2, nitrite, and nitrate test strips	[29]
Adenovirus	O3e	NA	NA	Not measured	Not measured	Optical spectrometer, UV power meter, photometric ozone analyzer	[47]
Influenza A and B virusesi	H2O2f	Yes	Yes	Hemagglutination assays, ELISA, Western blotting	RT-qPCR	Chemical indicator strips, multichannel spectrophotometer, gas detector	[48]
RSV	H2O2f	No	Yes	Immunochromatography kits	RT-PCR, RT-qPCR	Active O2 test strips	[31]
HIV	↑O2+, O, NO, N2 (second positive), N2+	NA	Yes	Not measured	qPCR	Optical emission spectroscopy	[33]
Animal viruses
NDV	↑ Oxidation/reduction potential, H2O2, OH•, NO•	Yes	Yes	Bradford protein assay kits	Agilent 2100 bioanalyzer	Oxidation/reduction potential probe, H2O2 assay kit, electrical conductivity meter, electron spin resonance	[38]
NDV, AIV	↑ Oxidation/ reduction potential, O, NO, OH	NA	NA	Not measured	Not measured	Oxidation/reduction potential probe, optical emission spectroscopy	[35]
Plant viruses
TMV	↑ H2O2, NO3−, HNO2, N2O2, NO2−	No	Yes	Western blotting	RT-PCR	Optical absorption spectroscopy, chemical probe	[45]
PVY	H2O2e, ↑OH, O	NA	Yes	Not measured	RT-PCR	Optical emission spectroscopy, H2O2 test strips	[7]

^aAbbreviations: ELISA, enzyme-linked immunosorbent assay; EMA, ethidium monoazide; FT-IR, Fourier-transform infrared; LC-MS, liquid chromatography-mass spectrometry; MS/MS, tandem mass spectrometry; NA, not applicable.

^b↑, The increase of RNS/ROS was measured but their importance for inactivation was not determined.

^cMeasurements of pH and temperature are excluded, as are scavenger experiments and other methods used for indirect identification of RONS.

^dMethods to determine modes of virus inactivation were applied only for treated solutions.

^ePlays a role in inactivation, but its importance was not defined.

^fMajor role in the inactivation.

^gMethods to determine modes of virus inactivation were applied only for plasma ignited in 99% Ar and 1% O₂.

^hImportant but does not have a main role in inactivation.

ⁱThe only group that reported degradation of viral envelope using FT-IR spectrophotometry. ELISA was performed only for influenza B; western blotting, RT-qPCR, hemagglutination, and FT-IR only for Influenza A.