STUDIES ON RESIDUE AND DEPLETION OF SARAFLOXACIN HYDROCHLORIDE IN Goldfish,CARASSIUS AURATUS

This study developed a method to detect sarafloxacin in goldfish(Carassius auratus) plasma and tissues using reverse phase high performance liquid chromatography(RP-HPLC).Plasma,muscle,skin,hepatopancreas,kidney and ovary were sampled at different intervals after oral administration of sarafloxacin hydrochloride at single dose of 20mg/kg under 21±2℃.Joining danofloxacin mesylate as inner standard,the medicine was extracted by dichloromethane from plasma and tissues,and the extracts were evaporated to dryness with N_2 flow in water bath of 60℃ then dissolved in mobile phase.The fat of the solute was degreased by hexane.Sarafloxacin hydrochloride and danofloxacin mesylate analyses were performed by RP-HPLC.The mobile phase was acetonitrile and 0.2mol/L phosphate buffer(pH7.4)(including 0.5% tetrabutyl ammonium bromide)(10/90,V/V) adjusted to pH 3.0 with phosphoric acid.Sarafloxacin hydrochloride and danofloxacin mesylate were quantitated by using ZORAX SB-C_(18) column and ultraviolet detector was set at 280nm.The mean recoveries were all higher than 82.97% for samples and inter-day CV for plasma and tissues were all under 8.41%,The lowest limit of detection was 0.0125μg/g for muscle.Both limit of detection(LOD) and limit of quantitation(LOQ) met the requirement of the residual detection.The results showed that the elimination rate was markedly different in plasma and five tissues of healthy female goldfish.The drug was slowly eliminated in plasma,the concentration of sarafloxacin hydrochloride in kidney and hepatopancreas was higher than other tissues and skin showed the slowest depletion among five tissues.Kidney was the main reservoir of sarafloxacin hydrochloride in goldfish.Withdrawl time was 14d when the maximum residue is 30μg/kg for edible tissues after single oral administration of sarafloxacin hydrochloride in healthy female goldfish.