Determination of allantoin in bovine milk by high-performance liquid chromatography

Determination of allantoin in bovine milk based on high-performance liquid chromatography (HPLC) is described. Following dilution and filtration, milk samples were analysed directly. Separation and quantification of allantoin was achieved using a Spherisorb 5 NH2 column (250 x 4.6 mm ID), acetonitrile-water (90:10, v/v) mobile phase at a flow-rate of 2.0 ml min(-1), temperature 20 degrees C and monitoring the effluent at 214 nm. Total analysis time was 10 min. Recovery of allantoin added to milk was 97 (+/-3.7, n = 30)%. Lowest detectable concentration was 1 micromol l(-1). Within-day and between-day variability were less than 3%. Advantages of improved retention and separation of allantoin, and less complicated sample preparation exist over current methods.