Premium
PHOTOSENSITIZATION BY DRUGS: NALIDIXIC AND OXOLINIC ACIDS
Author(s) -
MOORE DOUGLAS E.,
HEMMENS VIOLET J.,
YIP HELEN
Publication year - 1984
Publication title -
photochemistry and photobiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.818
H-Index - 131
eISSN - 1751-1097
pISSN - 0031-8655
DOI - 10.1111/j.1751-1097.1984.tb03404.x
Subject(s) - oxolinic acid , nalidixic acid , chemistry , photochemistry , singlet oxygen , photodissociation , aqueous solution , carboxylic acid , hydrogen bond , organic chemistry , oxygen , antibiotics , biochemistry , molecule , ciprofloxacin
— The antibacterial drugs, nalidixic acid and oxolinic acid, have been tested as photosensitizers in aqueous solution using 365 nm UV light. Absorption and fluorescence spectra indicate that intramolecular hydrogen bonding stabilizes the unionized form of these compounds in the pH region2–4. The ability of the unionized species to sensitize photooxidation by the type II (singlet oxygen) mechanism was found to be lower than when these drugs were ionized. Comparison withquinoline–3‐carboxylic acid and the methyl esters of nalidixic and oxolinic acids emphasised the significance of the hydrogen bonding in relation to the excited state properties. Unionized nalidixic acid undergoes photolysis more readily than the ionized form, apparently by a free radical mechanism, while oxolinic acid is more stable.