title: Evaluation of the phototransformation of the antiviral zanamivir in surface waters through identification of transformation products.
abstract: The antiviral zanamivir has been recently reported to occur in surface waters where its presence may lead to the selection of resistant strains of virus in aquatic fauna. In order to evaluate the fate of zanamivir in surface waters, its susceptibility to phototransformation was evaluated using simulated and natural sunlight. Upon exposure of aqueous solutions (20μgL(-1)) to simulated sunlight, zanamivir in surface water degraded at t1/23.6h. Under natural sunlight in surface water about 30% of the initial concentration of the antiviral disappeared within 18 days. The experiments with surface water showed similar effect as humic acid addition with expected decreasing effect on degradation while nitrate addition showed increasing effect. In the experiments with artificial sunlight at high concentrations of zanamivir, four photoproducts were tentatively identified by hydrophilic interaction chromatography-LTQ-Orbitrap-MS, showing [M+H](+) ions at m/z 112 (TP111), m/z 275 (TP274), m/z 323 (TP322), and m/z 333 (TP332). However at 20μgL(-1) only the formation of the recalcitrant TP111 was observed. The proposed structures were rationalized by photolysis mechanisms. Photoproduct TP111 was confirmed with a commercially available standard (isocytosine). In summary, the findings suggest that the photodegradation of zanamivir in surface waters proceeds with slow kinetics.
authors.affiliation: Water and Soil Quality Research Group, IDAEA-CSIC, c/ Jordi Girona, 18-26, 08034 Barcelona, Spain.
authors.forename: Bozo
authors.initials: B
authors.lastname: Zonja
authors.affiliation: IAREN - Water Institute of the Northern Region, Rua Dr. Eduardo Torres, 229, 4450-113 Matosinhos, Portugal; Laboratory of Hydrology, Faculty of Pharmacy, University of Porto, Rua Aníbal Cunha, 164, 4050-047 Porto, Portugal.
authors.forename: Carlos
authors.initials: C
authors.lastname: Gonçalves
authors.affiliation: Water and Soil Quality Research Group, IDAEA-CSIC, c/ Jordi Girona, 18-26, 08034 Barcelona, Spain. Electronic address: spsqam@cid.csic.es.
authors.forename: Sandra
authors.initials: S
authors.lastname: Pérez
authors.affiliation: University of Barcelona (UB), Faculty of Pharmacy; Unit of Medicinal Chemistry (Associated to CSIC), Avda. Joan XXIII, s/n, 08028 Barcelona, Spain; Institute of Advanced Chemistry of Catalonia (IQAC-CSIC), Research Unit on Bioactive Molecules (RUBAM), Department of Biomedicinal Chemistry, Jordi Girona 18-26, 08034 Barcelona, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Delgado
authors.affiliation: ICREA, Passeig Lluis Companys 23, 08010 Barcelona, Spain; ICRA, C/ Emili Grahit, 101, Edifici H2O, 17003 Girona, Spain.
authors.forename: Mira
authors.initials: M
authors.lastname: Petrovic
authors.affiliation: IAREN - Water Institute of the Northern Region, Rua Dr. Eduardo Torres, 229, 4450-113 Matosinhos, Portugal; Laboratory of Hydrology, Faculty of Pharmacy, University of Porto, Rua Aníbal Cunha, 164, 4050-047 Porto, Portugal.
authors.forename: Maria Fátima
authors.initials: MF
authors.lastname: Alpendurada
authors.affiliation: Water and Soil Quality Research Group, IDAEA-CSIC, c/ Jordi Girona, 18-26, 08034 Barcelona, Spain; ICRA, C/ Emili Grahit, 101, Edifici H2O, 17003 Girona, Spain.
authors.forename: Damià
authors.initials: D
authors.lastname: Barceló
mesh_terms: D000998:Antiviral Agents / Q000528:radiation effects*; D007700:Kinetics; D010782:Photolysis; D045483:Rivers; D013472:Sunlight; D014874:Water Pollutants, Chemical / Q000528:radiation effects*; D053243:Zanamivir / Q000528:radiation effects*
chemical_list: D000998:Antiviral Agents; D014874:Water Pollutants, Chemical; D053243:Zanamivir
keywords: High resolution; LC–MS; Pharmaceutical; Photodegradation; Transformation products and pathways