Studies On The Determination Of Nicarbazin Residues By HPLC And Its Residue Elimination In Chicken Tissues

Nicarbazin is a kind of broad-spectrum insecticide, which is used for the prevention of coccodiosis in poultry. DNC is the residue marker of Nicarbazin, and the MRLs of Nicarbazin in Chicken tissues have been regulated as 200μg/kg.This study developed a HPLC method for the determination of DNC residues in chicken muscle,liver and kidney. It also focused on DNC residue elimination of in chicken tissues. Tissue samples were extracted with acetonitrile, purified with liquid-liquid extraction and an Alumina-B SPE chromatography, washed by chloroform, and eluted by acetonitrile-methanol (90/10, v/v). Eluate was evaporated to dryness, dissolved in acetonitrile-water (50/50, v/v) and filtered. DNC was determined on an ODS column with ultraviolet absorption detection at 340 nm, using acetonitrile-water (50/50, v/v) as eluent. DNC concentration had a good linear coefficient relation ( r = 0.9999) in the range of 0.04~50.0 mg/L. When DNC was added to tissues at 0.1,0.2 and 0.4 mg/kg, the average recoveries in muscle was 80.21±0.95%; the average recoveries in liver was 75.37±5.04%, and the average recoveries in kidney was 78.84±2.78%. The within-day coefficient of variation (CV) and between-day CV were less than 7% and 10% respectively. In this condition,the limit of detection was 0.02 mg/kg. This method could meet the demand of residue determination of DNC in chicken tissues.In order to study the residue elimination of Nicarbazin in chicken tissues, Nicarbazin was fed to Huangyu broiler for 2 weeks at clinical recommended dose (125 mg/kg), and then the concentrations of DNC in chicken tissues were detected by the method introduced above. The results indicated that the liver was the target tissue of DNC residues. DNC residues in muscle and kidney were at comparative low levels, and were eliminated faster than that in liver. The results also showed that the DNC residues in all tissues were less than 200μg/kg or not detectable after 96 hours withdrawal time. According to the usual methods of calculation for the withdrawal time in our country, the withdrawal time for Nicarbazin was advised as 4 days in chicken.