Abstract
The interaction of 8-methoxypsoralen (8-MOP) with synthetic eumelanin was investigated using static and time-resolved fluoresence and pulsed photoacoustic calorimetry. Spectroscopic data indicate the absence of interaction in the ground state, whereas the singlet excited state of 8-MOP is quenched by the pigment; the average fluorescence lifetimes are independent of the melanin concentration, thus indicating a static mechanism. Photoacoustic data show that the quenching process involves an increased intersystem crossing probability, which is almost unaffected by the presence of oxygen, as expected for a molecule essentially acting as a type I photosensitizing agent.
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Losi, A., Viappiani, C. & Crippa, P.R. Quenching of the excited states of 8-methoxypsoralen by synthetic Eumelanin. J Fluoresc 3, 191–194 (1993). https://doi.org/10.1007/BF00862741
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DOI: https://doi.org/10.1007/BF00862741