title: Stability of fluoroquinolone antibiotics in river water samples and in octadecyl silica solid-phase extraction cartridges.
abstract: Intensive use of antibiotics in human and veterinarian medicine and in industrial farming (food additives) has resulted in the transport of important quantities of the active ingredients to environmental waters. Environmental analysis usually requires sample storage for certain periods of time and, consequently, it is of great importance to know the stability of antibiotics in these kinds of sample. Thus, in this work the stability in river water of oxolinic acid (Oxo) and ciprofloxacin (Cip), taken as representatives of fluoroquinolone and quinolone antibiotics respectively, has been evaluated. The stability of these compounds in river water has been studied both in containers and on C(18) solid-phase extraction cartridges (SPE) under different storage conditions (time, light, and temperature). Data analysis revealed that Cip and Oxo have different degradation profiles with different degradation kinetics in river water. It was also concluded that these antibiotics are stable both in the containers and on SPE cartridges for at least 2 weeks at ambient temperature, and stability can be increased substantially if samples are stored at low temperatures (4 and -18 degrees C).
authors.affiliation: Institute for Reference Materials and Measurements, Joint Research Centre, European Commission, Retieseweg, 2440 Geel, Belgium. esthert@quim.ucm.es
authors.forename: Esther
authors.initials: E
authors.lastname: Turiel
authors.forename: Antonio
authors.initials: A
authors.lastname: Martín-Esteban
authors.forename: Guy
authors.initials: G
authors.lastname: Bordin
authors.forename: Adela R
authors.initials: AR
authors.lastname: Rodríguez
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004355:Drug Stability; D004784:Environmental Monitoring / Q000379:methods; D024841:Fluoroquinolones / Q000737:chemistry*; D005618:Fresh Water / Q000737:chemistry*; D007700:Kinetics; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry*; D013997:Time Factors; D014873:Water Pollutants / Q000032:analysis*
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D014873:Water Pollutants; C026679:octadecylsilica; D012822:Silicon Dioxide