Research On Three Kinds Of Quinolones Residues Determination In Oreochomis Niloticus Linn And Evaluation Of The Residual Risk

The residues of norfloxacin, ciprofloxacin and enrofloxacin in fishery products broke the safety of fishery products. To establish a novel method to measure the residues of norfloxacin, ciprofloxacin and enrofloxacin, we focus on the study as follows:1. The assay method of norfloxacin, ciprofloxacin and enrofloxacin residues in Oreochomis niloticus Linn tissues by high performance liquid chromatography was studied. The samples were dehydrated by sodium sulfate and the quinolones were abstracted in acid acetonitrile by gyratory shaker. The fat was extracted into hexane. The samples were concentrated by rotary evaporator. The other residues in the samples were removed by centrifuging. The minimum detectable amount of norfloxacin, ciprofloxacin and enrofloxacin were 5.0μg/kg, 1.0μg/kg and 5.0μg/kg respectively. The standard curve formula were:y=61.803x-0.5808, y=73.620x+0.425 and y=78.343x-1.024 respectively. The averaged recoveries ranged from 89.80%-91.40%,81.88%-87.73% and 91.19%-95.70%. The relative standard deviations were 3.89%-5.31%,2.97%-3.36% and 2.84%-5.29% respectively. The method was proved to be sensitive, rapid, precise, economical and applied.2. A test was designed to analyze the probability of evaluating the drug residual risk in fishery products by the dose proportionality method. Based on power model, common hypothesis-testing approaches and confidence interval criteria were applied to assess whether there were dose proportionality for ciprofloxacin in the intesttine, liver, plasma and muscle tissue of Oreochomis niloticus Linn. The results showed:in the dosages varying from 20mg-kg-1-80mg-kg-1 for ciprofloxacin, it showed the dose proportionality in liver while no dose proportionality was found in intestine, plasma and muscle. The fitting formula for AUC and Dosage was AUC=0.162D1409 while R2=0.901. It suggested that liver may be applied as the target organ to evaluate the residual risk of ciprofloxacin in Oreochomis niloticus Linn. This method provied us a novel idea to assess the drug residues risk in fishery products.