Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has had a profound impact on humanity. Prevention of infection by disinfecting surfaces and aerosols using non-chemical methods is highly desirable. Ultraviolet C (UVC) light is uniquely positioned to achieve pathogen inactivation.in new paper in a diary ACS PhotonicsScientists have reported the inactivation of the SARS-CoV-2 virus by UVC radiation and are investigating the mechanism.
David other. demonstrated inactivation of SARS-CoV-2 by 266 nm UVC light. This closely matches the absorption spectra of RNA and aromatic amino acids.Image credit: David other., doi: 10.1021/acsphotonics.3c00828.
The COVID-19 pandemic caused by SARS-CoV-2 spreads through nosocomial, public, and workplace-based infections.
Transmission is thought to be direct through respiratory droplets or indirect through fomites, leading to increased interest in virus disinfection.
The SARS-CoV-2 virion consists of a core of nucleic acid strands containing the virus's genetic information, surrounded by a lipid membrane with protruding protein spikes. Each component is required for infection.
In the new study, Sumeet Mahajan and colleagues at the University of Southampton investigated how ultraviolet laser light affects each of these key components and destroys the virus.
By using special lasers with two different wavelengths, they were able to see how each viral component breaks down under bright light.
They found that the genomic material was highly sensitive to degradation, and the protein spike lost the ability to bind to human cells.
UV light includes UVA light, UVB light, and UVC light. Very little UVC light with frequencies below 280 nm reaches the Earth's surface from the sun.
The authors used UVC light in their study, which is less studied because of its antiseptic properties.
UVC light is strongly absorbed by various viral components, such as genetic material (about 260 nm) and protein spikes (about 230 nm), allowing the team to choose laser frequencies of 266 nm and 227 nm for this project.
Researchers found that low-power 266nm light causes RNA damage and affects the genetic information of viruses.
266 nm light also damaged the structure of the SARS-CoV-2 spike protein, reducing its ability to bind to human cells by breaking disulfide bonds and aromatic amino acids.
Although 227 nm light was less effective at inducing RNA damage, it was effective at damaging proteins through oxidation, a chemical reaction involving oxygen that unravels protein structures.
Importantly, SARS-CoV-2 has one of the largest genomes of any RNA virus. This makes them particularly sensitive to genomic damage.
“Inactivating airborne viruses with light provides a versatile tool for disinfecting public spaces and sensitive equipment that is difficult to decontaminate using traditional methods,” Professor Mahajan said.
“We found differences in the susceptibility of the molecular components of the virus to light inactivation. This opens up the possibility of fine-tuned disinfection techniques.”
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George David other. Mechanism of SARS-CoV-2 inactivation using UVC laser irradiation. ACS Photonics, published online on December 25, 2023. doi: 10.1021/acsphotonics.3c00828
Source: www.sci.news
