Study on the Detection Method of Oxolinic Acid and Flumequine Residues in Chicken Tissues

The method of high-performance liquid chromatography (HPLC) with fluorescence detection wasused for the simultaneous determination of oxolinic acid and flumequine residues in chicken tissues. The drugswere extracted with 0.1 mol/L aqueous potassium dihydrogenphosphate, purified and concentrated by passingthrough Bond Elut C18 solid-phase extraction cartridges. The HPLC separation was carried out on a Luna C18 5μmcolumn (150 mm×4.6 mm i.d.) with 0.02 mol/L phosphoric acid - acetonitrile - tetrahydrofuran (69∶16∶15)as the mobile phase. A fluorescence detector was used at an excitation wavelength of 325 nm and an emissionwavelength of 369 nm. The calibration graphs were linear between 10 ng/mL and 500 ng/mL for oxolinic acid andflumequine. Average recoveries of the drugs from chicken tissues fortified at a level of 20~300 ng/g were 61%~92%.Coeffcients of variation were 15%, and the detection limits for oxolinic acid and flumequine were 20 ng/g.