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PubMed · 1904490

Temperature effects on photosensitized processes.

V Gottfried·S Kimel
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Abstract

The singlet-oxygen-mediated reaction of meso-tetraphenylporphine tetrasulphonate (TPPS4) with different chemical acceptors in buffered aqueous solution was studied as a function of temperature. Imidazole, tryptophan, dimethyl p-nitrosoaniline, (RNO) and furfuryl alcohol served as acceptors. The measurements were performed in real time by spectroscopic or electrochemical monitoring of the consumption of the various reagents, acceptors or dissolved oxygen as a function of the absorbed energy. The results show the following increases in the reaction rate over the temperature range 15-45 degrees C: tryptophan (86%), RNO (90%), furfuryl alcohol (150%) and imidazole (210%). The influence of temperature-correlated changes in the initial oxygen concentration and pH was investigated. Possible implications of the present results for the synergistic influence of hyperthermia and photodynamic therapy are discussed.

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Indicators and ReagentsKineticsLightPorphyrinsRadiation-Sensitizing AgentsSolutionsSpectrometry, FluorescenceThermodynamicsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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V Gottfried, S Kimel. 1991. Temperature effects on photosensitized processes.. https://doi.org/10.1016/1011-1344(91)80116-y

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