DETERMINATION OF RESIDUES OF FLUMEQUINE AND 7-HYDROXYFLUMEQUINE IN EDIBLE SHEEP TISSUES BY LIQUID-CHROMATOGRAPHY WITH FLUOROMETRIC AND ULTRAVIOLET DETECTION

A simple, sensitive, and rapid method for simultaneous determination o f residues of flumequine and its microbiologically active metabolite 7 -hydroxyflumequine in 100 mg sheep edible tissues (muscle, liver, kidn ey, and fat) by liquid chromatography is reported. After liquid-liquid cleanup with ethyl acetate, tissue extracts were injected onto a Sele ct B column. The 2 compounds were determined by ultraviolet and fluori metric detection. The method was repeatable and reproducible for flume quine and 7-hydroxyflumequine in muscle, liver, kidney, and fat, with limits of detection below 2 and 3 mu g/kg for flumequine and 7-hydroxy flumequine, respectively. Mean recoveries for flumequine were 90 +/- 7 , 82 +/- 7, 89 +/- 5, and 82 +/- 6% in muscle, liver, kidney, and fat, respectively. Mean recoveries for 7-hydroxyflumequine were 91 +/- 2, 90 +/- 4, 86 +/- 3, and 84 +/- 4% in muscle, liver, kidney, and fat, r espectively.