Liquid chromatographic determination of the anticoccidial drug halofuginone hydrobromide in eggs

A liquid chromatographic (LC) method is described for the determination of 5-100 ppb halofuginone hydrobromide (HFG) in eggs. HFG as the free base is extracted from eggs with ethyl acetate. The extract is cleaned up on an acidic Celite 545 column. A Waters C18 column is used for LC separation with UV determination at 243 nm. The isocratic mobile phase is a mixture of water-acetonitrile-ammonium acetate buffer (12 + 5 + 3) and acetic acid. The interassay average recovery from eggs was 90.4%, with a standard deviation of 5.11 and a relative standard deviation of 5.65%.