Chu Pak-Sin, Wang Ro-Chen, Chu Hiufung V
Center for Veterinary Medicine, U.S. Food and Drug Administration, 8401 Muirkirk Road, Laurel, Maryland 20708, USA.
J Agric Food Chem. 2002 Jul 31;50(16):4452-5. doi: 10.1021/jf0202032.
A liquid chromatographic method was developed for the determination of ciprofloxacin, enrofloxacin, and sarafloxacin at 10-200 ppb in both egg yolk and egg albumen of laying hens. Egg yolk or albumen was acidified with 1 M phosphoric acid followed by deproteination with acetonitrile and centrifugation. The supernate was pipetted out, and the remaining protein pellet was extracted three times with acetonitrile. The supernates were combined and concentrated at 50 degrees C to <0.7 mL. The final volume was adjusted to 2 mL with 0.02 M potassium phosphate buffer, pH 2.5. Separation of the analytes was achieved using reversed-phase HPLC with fluorometric detection. The recoveries were >80% and coefficients of variation <20%. After validation, the method was applied for use in a national survey for fluoroquinolones in table eggs. Of the 276 eggs assayed, none was found positive for fluoroquinolones. The findings suggest that illegal use of fluoroquinolones in laying hens is not widespread.
建立了一种液相色谱法，用于测定蛋鸡蛋黄和蛋清中浓度为10 - 200 ppb的环丙沙星、恩诺沙星和沙拉沙星。用1 M磷酸酸化蛋黄或蛋清，然后用乙腈进行蛋白质沉淀并离心。吸出上清液，剩余的蛋白质沉淀用乙腈萃取3次。合并上清液并在50℃浓缩至<0.7 mL。用pH 2.5的0.02 M磷酸钾缓冲液将最终体积调至2 mL。采用反相高效液相色谱荧光检测法实现分析物的分离。回收率>80%，变异系数<20%。经过验证后，该方法应用于全国范围内的食用鸡蛋中氟喹诺酮类药物的调查。在检测的276个鸡蛋中，未发现氟喹诺酮类药物呈阳性。研究结果表明，蛋鸡中非法使用氟喹诺酮类药物的情况并不普遍。
