Simultaneous determination of flumequine and oxolinic acid in chicken tissues by solid phase extraction and capillary electrophoresis

This paper describes capillary electrophoresis (CE) methodology for simultaneous determination of oxolinic acid (OXO) and flumequine (FLU) in spiked chicken tissue using norfloxacin (NOR) as internal standard (IS), with diode array detection. The analytes were extracted using dichlorometane and NaOH and pre-concentrated by solid phase extraction (SPE). The recoveries obtained were 94 and 84% for oxolinic acid and flumequine, respectively. The detection and quantification limits achieved were 15 and 48 mug kg(-1) for oxolinic acid, respectively, and 10 and 30 mug kg(-1) for flumequine. The sensitivity of the method proposed allows the determination of these drugs at a residue level far below their maximum residue limit (MRL) established by the European Union (EU). (C) 2002 Elsevier Science B.V. All rights reserved.