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Method for the Assessment of Effects of a Range of Wavelengths and Intensities of Red/near-infrared Light Therapy on Oxidative Stress In Vitro
Published on: March 21, 2015
Wavelength dependence and wavelength selectivity in photochemical reactions
Stefano Protti1, Davide Ravelli1, Maurizio Fagnoni1
1PhotoGreen Lab, Department of Chemistry, University of Pavia, viale Taramelli 12, 27100 Pavia, Italy. fagnoni@unipv.it.
Abstract:
The concepts of wavelength dependence and wavelength selectivity have been commonly used by organic photochemists for a long time. The aim of the present article is to offer a selection of relevant cases where the choice of the irradiation wavelength played a key role in the outcome of a photochemical path. Wavelength dependence can be related to the variation in the efficiency (but not the fate) of a process. Herein, three cases have been recognized where a wavelength-selectivity paradigm operates. Indeed, a different wavelength may (i) activate a different chromophore in a single molecule, (ii) induce the population of different reactive excited states and (iii) sequentially populate the excited state of a compound and the excited state of an intermediate photogenerated from it, which show a different reactivity.
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