What is the dominant (killing) interaction between UV-C radiation from mercury low-pressure germicide lamp (wavelength 253,7 nm) and COVID-19 virus that is only about 120 nm large ? The 253,7 nm radiation (photon energy 4,9 eV) is not considered as ionizing radiation.
UV light can cause thymine bases to fuse together, scrambling the DNA sequence. Since the DNA sequence is no longer correct, it can no longer replicate properly. This is how UV light annihilates viruses, by destroying their ability to reproduce.
Yes, it works by ionizing the double bonds in the RNA bases. The RNA absorbance maximum is 260nm, almost exactly coincident with your lamp. Careful, you can get a sunburn from it, as your DNA absorbs at the same wavelength!
Jan Balaz
UV spectrum has UV-A, -B and -C. UV-C ( typically at 254 nm ) can be used to kill germs, including coronavirus. However, UV-C can also hurt human skins. Now, scientists are into the newer play tool far-UV-C, which can effectively kill germs and not hurt skins.
See below paper:
https://www.researchsquare.com/article/rs-25728/v1 (2020)
Hi!! For the disinfection of a dental office, how many watts are needed? do you know where can i read about that?
UVC is strongly absorbed by RNA bases of SARS-CoV-2 leading to molecular structural damage via a photodimerization process. This results in virus inactivation, such that it is no longer able to replicate.
https://in.dental-tribune.com/news/how-to-use-ultraviolet-light-uvc-to-fight-covid-19-effectively-in-dental-clinics-dr-ajay-bajaj/
Dear Jan,
appended you will find some slides from my lecture. If you are interested in UC radiation sources you can find more at my RG page.
Alle the best,
Thomas
Don't forget skin cancer with long-term exposure. (Cataracts and macular degeneration too)(no one likes actinic keratoses)