UNIGE document Scientific Article
previous document  unige:27494  next document
add to browser collection

Photochemistry of aqueous solutions of kynurenic acid and kynurenine yellow

Zelentsova, Ekaterina A.
Snytnikova, Olga A.
Kaptein, Robert
Tsentalovich, Yuri P.
Published in Photochemical and Photobiological Sciences. 2013, vol. 12, no. 3, p. 546-558
Abstract The photophysics and photochemistry of kynurenic acid (KNA) and kynurenine yellow (KNY) in neutral aqueous solutions were investigated using time-resolved optical spectroscopy. Both molecules have similar quinoline-like structures, the only difference being the absence of conjugation in the nitrogen containing cycle in KNY. The main channel of S1 excited state decay in the case of partially-unconjugated KNY is the solvent assisted S1 → S0 radiationless transition via intermolecular hydrogen bonds (ΦIC = 0.96), whereas, in the case of fully-conjugated KNA, it is intersystem crossing to the triplet state (ΦT = 0.82). The major intermediate products of the singlet excited KNY deactivation are the triplet state (ΦT = 0.022) and, most probably, the enol form (Φenol = 0.012), which decay with the formation of 2,3-dihydro-4-hydroxyquinoline and 4-hydroxyquinoline, respectively. The results obtained show that KNA and KNY, which are products of the decomposition of the UV filter kynurenine, are significantly more photoactive and less photostable than the parent molecule.
Full text
Article (Published version) (2 MB) - document accessible for UNIGE members only Limited access to UNIGE
Other version: http://xlink.rsc.org/?DOI=c2pp25357g
Research group Groupe Vauthey
(ISO format)
ZELENTSOVA, Ekaterina A. et al. Photochemistry of aqueous solutions of kynurenic acid and kynurenine yellow. In: Photochemical and Photobiological Sciences, 2013, vol. 12, n° 3, p. 546-558. https://archive-ouverte.unige.ch/unige:27494

248 hits

0 download


Deposited on : 2013-04-17

Export document
Format :
Citation style :