Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 3, 2013
Previous Article Next Article

Photochemistry of aqueous solutions of kynurenic acid and kynurenine yellow

Author affiliations

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.

Graphical abstract: Photochemistry of aqueous solutions of kynurenic acid and kynurenine yellow

Back to tab navigation

Supplementary files

Article information


Submitted
25 Oct 2012
Accepted
02 Dec 2012
First published
03 Dec 2012

Photochem. Photobiol. Sci., 2013,12, 546-558
Article type
Paper

Photochemistry of aqueous solutions of kynurenic acid and kynurenine yellow

E. A. Zelentsova, P. S. Sherin, O. A. Snytnikova, R. Kaptein, E. Vauthey and Y. P. Tsentalovich, Photochem. Photobiol. Sci., 2013, 12, 546
DOI: 10.1039/C2PP25357G

Social activity

Search articles by author

Spotlight

Advertisements