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Updated: Aug 30, 2026

Inactivation of Pathogens via Visible-Light Photolysis of Riboflavin-5′-Phosphate
Published on: April 6, 2022
Activation of molecular oxygen by infrared laser radiation in pigment-free aerobic systems
A A Krasnovsky1, N N Drozdova, A V Ivanov
1Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow 119071, Russia. phoal@mail.ru
Abstract:
With the goal of mimicking the mechanisms of the biological effects of low energy laser irradiation, we have shown that infrared low intensity laser radiation causes oxygenation of the chemical traps of singlet oxygen dissolved in organic media and water saturated by air at normal atmospheric pressure. The photooxygenation rate was directly proportional to the oxygen concentration and strongly inhibited by the singlet oxygen quenchers. The maximum of the photooxygenation action spectrum coincided with the maximum of the oxygen absorption band at 1270 nm. The data provide unambiguous evidence that photooxygenation is determined by the reactive singlet (1)Delta(g )state formed as a result of direct laser excitation of molecular oxygen. Hence, activation of oxygen caused by its direct photoexcitation may occur in natural systems.
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