Determination of sulfamethazine residue in chicken serum and egg by high-performance liquid chromatography with chemiluminescence detection.

A sensitive method that involves high-performance liquid chromatography with chemiluminescence detection is developed for the determination of sulfamethazine residue in samples of chicken serum and egg. Sulfamethazine is extracted from the samples and derivatized with fluorescamine. The derivatized samples are eluted by reversed-phase chromatography using a mixture of 10mM potassium phosphate and 30% acetonitrile on a Nova-Pak C 18 column. The post-column reagents in the chemiluminescence system are 1mM bis[2-(3,6,9-trioxadecanyloxycarbonyl)-4-nitrophenyl] oxalate and 0.3M hydrogen peroxide in acetonitrile. The detection limit in the standard solution is 1 ng/mL, and the calibration curve is linear between 1 and 100 ng/mL. The recoveries of spiked samples (50 ppb) are 95.8 ± 9.7% in chicken serum samples and 84.9 ± 10.7% in egg samples. In actual sample analysis, the lowest detectable concentration of sulfamethazine (0.073 μg/mL) was found at 48 h in serum and on day 9 (0.017 μg/g) in egg after oral administration of a dose of 100 mg/kg body weight to hens.