Mechanism of UV photodegradation of fluoroquinolone antibiotic ciprofloxacin in aqueous solutions.

Autor: Tyutereva YE; Voevodsky Institute of Chemical Kinetics and Combustion SB RAS, 630090, 3 Institutskaya str., Novosibirsk, Russian Federation., Snytnikova OA; International Tomography Center SB RAS, 630090, 3a Institutskaya str., Novosibirsk, Russian Federation., Sheven DG; Nikolaev Institute of Inorganic Chemistry SB RAS, 630090, Acad. Lavrentieva Ave. 3, Novosibirsk, Russian Federation., Fedunov RG; Voevodsky Institute of Chemical Kinetics and Combustion SB RAS, 630090, 3 Institutskaya str., Novosibirsk, Russian Federation., Yanshole VV; International Tomography Center SB RAS, 630090, 3a Institutskaya str., Novosibirsk, Russian Federation., Grivin VP; Voevodsky Institute of Chemical Kinetics and Combustion SB RAS, 630090, 3 Institutskaya str., Novosibirsk, Russian Federation., Pozdnyakov IP; Voevodsky Institute of Chemical Kinetics and Combustion SB RAS, 630090, 3 Institutskaya str., Novosibirsk, Russian Federation. Electronic address: ipozdnyak@kinetics.nsc.ru.
Jazyk: angličtina
Zdroj: Chemosphere [Chemosphere] 2024 Nov; Vol. 367, pp. 143643. Date of Electronic Publication: 2024 Nov 01.
DOI: 10.1016/j.chemosphere.2024.143643
Abstrakt: Mechanism of direct UV photolysis of the zwitterionic and anionic forms of the quinolone antibiotic ciprofloxacin (CIP) was revealed by combination of nanosecond laser flash photolysis, steady-state photolysis coupled with high resolution LC-MS and DFT quantum-chemical calculations. For both forms, the main intermediate is a dissociative triplet state, which loses a fluorine ion to form a triplet carbocation; subsequent solvent attack of the latter leads to the formation of products of hydroxylation both the aromatic ring and the piperazyl substituent. Correspondingly, the quantum yield of photolysis of both CIP forms does not depend on the excitation wavelength, but depends on the concentration of dissolved oxygen. Secondary photolysis leads to a number of products of oxidation of the aromatic system, as well as oxidation, opening and full destruction of the piperazinyl substituent. The results obtained may be important for understanding the fate of quinolone antibiotics in UVC disinfection processes and in natural waters under the action of sunlight.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024 Elsevier Ltd. All rights reserved.)
Databáze: MEDLINE
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