Determination of total taurine in pet foods by liquid chromatography of the dansyl derivative: Collaborative study

A liquid chromatographic (LC) method for the determination of total taurine in pet foods was evaluated in a collaborative study. Ten laboratories assa yed 6 blind duplicate pairs of wet and dry pet foods. The taurine in the 6 sample pairs ranged from low (170 mg/kg) to high (2250 mg/kg) concentration s as is. Collaborators also assayed a sample of known taurine concentration for familiarization purposes. Samples were hydrolyzed to release bound tau rine, which was subsequently converted to the dansyl derivative and quantit ated by gradient-elution LC with fluorescence detection. Repeatability rela tive standard deviations, RSDr ranged from 3.2 to 10.0%; reproducibility re lative standard deviations, RSDR, ranged from 6.1 to 16.1%. The method has been adopted Official First Action status by AOAC INTERNATIONAL.