Systematic analysis of synthetic antibacterials in chicken muscles and eggs by high performance liquid chromatography

A high performance liquid chromatographic method was developed for determining eleven synthetic antibacterials in chickens and eggs. Synthetic antibacterials in the acetonitrile extract from chicken muscle and egg were adsorbed on an alumina column and were eluted with 10ml of 85% methanol and then with 25ml of a mixture of methanol, acetic acid and water (30:0.4:70) as fraction I (sulfa drugs). The 85% methanol eluate was passed through a SEP-PAK C18 column. Clopidol, dinitolmide and ethopabate were eluted with 15ml of 20% acetonitrile as fraction II, and then nicarbazin and pyrimethamine were eluted with 20ml of a mixture of acetnitrile, acetic acid and water (40:1:60) as fraction III. Each fraction was quantitatively analyzed by high performance liquid chromatography. The detection limit of each drug was 0.05ppm in chicken muscles and eggs. The average recoveries of all drugs added to chicken muscles and eggs were more than 80%.