title: Trace determination of beta-lactam antibiotics in environmental aqueous samples using off-line and on-line preconcentration in capillary electrophoresis.
abstract: A sensitive and reliable method using capillary zone electrophoresis with UV-diode array detection (CZE-DAD) has been developed and validated for trace determination of beta-lactam antibiotics in waste, well and river water matrices. Due to the lack of sensitivity of the UV-vis detection, a solvent extraction/solid-phase extraction (SPE) method applied for off-line preconcentration and cleanup of water samples, in combination with an on-line preconcentration methodology named large volume sample stacking (LVSS) have been applied. The analytes included nafcillin, dicloxacillin, cloxacillin, oxacillin, ampicillin, penicillin G and amoxicillin. Average recoveries for water samples fortified with the studied beta-lactams at different concentration levels (1.0, 2.0 and 4.0 microg/L) were ranging between 94 and 99%, with relative standard deviations (RSDs) lower than 10%. The precision, calculated as intra-day and inter-day standard deviations fell within acceptable ranges (3.3-7.2%). The limits of detection were estimated to range between 0.08 and 0.80 microgL(-1) for the studied compounds. All the samples analyzed were negative for all the analytes at these levels of concentration and the method showed its usefulness for the detection of these widely applied beta-lactam antibiotics in different kinds of waters.
authors.affiliation: Department of Analytical Chemistry, Faculty of Sciences, Campus Fuentenueva, s/n, E-18071 Granada, Spain.
authors.forename: M I
authors.initials: MI
authors.lastname: Bailón-Pérez
authors.forename: A M
authors.initials: AM
authors.lastname: García-Campaña
authors.forename: C
authors.initials: C
authors.lastname: Cruces-Blanco
authors.forename: M
authors.initials: M
authors.lastname: del Olmo Iruela
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis* / Q000737:chemistry; D019075:Electrophoresis, Capillary / Q000379:methods*; D004777:Environment; D004784:Environmental Monitoring / Q000379:methods*; D012680:Sensitivity and Specificity; D052616:Solid Phase Extraction / Q000379:methods*; D014867:Water / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D047090:beta-Lactams / Q000032:analysis* / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D014874:Water Pollutants, Chemical; D047090:beta-Lactams; D014867:Water