Science and Technology Production
Article
Authorship
Federico R. Conde
;
María S. Churio
;
PREVITALI, CARLOS MARIO
Date
2004
Publishing House and Editing Place
Royal Chemical Society
Magazine
Photochemical and Photobiological Sciences,
vol. 3
(pp. 960-967)
Royal Chemical Society
Summary
Information provided by the agent in
SIGEVA
In vitro studies on the structurally related mycosporine-like amino acids (MAAs) porphyra‑334 and shinorine in aqueous solutions were carried out aiming at their full photochemical and photophysical characterization and expanding the evidence on the assigned UV-photoprotective role of the molecules in vivo. The experiments on shinorine confirmed a high photostability and a poor fluorescence quantum yield, in concordance with previous results on porphyra-334. The estimation of triplet prod...
In vitro studies on the structurally related mycosporine-like amino acids (MAAs) porphyra‑334 and shinorine in aqueous solutions were carried out aiming at their full photochemical and photophysical characterization and expanding the evidence on the assigned UV-photoprotective role of the molecules in vivo. The experiments on shinorine confirmed a high photostability and a poor fluorescence quantum yield, in concordance with previous results on porphyra-334. The estimation of triplet production quantum yields for both MAAs was achieved by laser-flash photolysis measurements. In particular, photosensitization experiments on porphyra-334 support the participation of the triplet state in the photodecomposition mechanism yielding a more precise value of FT. As well, photoacoustic calorimetry experiments allowed the first direct quantification of the nonradiative relaxation pathways of the excited MAAs in solution, corroborating that the vast majority (ca. 97 %) of the absorbed energy is promptly delivered to the surroundings as heat, consistently with the low photodecomposition and emission yields observed.
Show more
Show less