Effect of ultraviolet radiation from a pulsed ArF laser on the viability of microfungi

The effect of ultraviolet radiation from a pulsed excimer argon fluoride (ArF) laser on the viability of microfungi spores grown in polar latitudes was studied at a radiation wavelength of 193 nm and pulse width of 15 ns. The radiant exposures required to cause the inactivation of spore monolayers of various micromycete species were determined. The viability of the irradiated microfungi spores was found to be affected by the species composition, presence of melanin in the cell wall, and the age of the micromycete culture. Changes in the surface structure of the spores during laser processing were detected via atomic force microscopy. The results of this work indicate the existence of two parallel mechanisms that result in the destruction of spores—namely, a photochemical and a photothermal process—with the latter mechanism playing the predominant role.