Abstract
Analysis of Nτ-methylhistidine is intricate and time consuming. In the present study, a modified technique using high-performance liquid chromatography, which utilizes a reversed-phase separation with ion pairing and post column fluorescence derivatization for the analysis of Nτ-methylhistidine in chicken feed and excreta is described. Two ml of the hydrolyzed sample was applied directly into the ion-exchange resin column without evaporation of HCl to roughly separate Nτ-methylhistidine from acidic and neutral amino acids. The Nτ-methylhistidine fraction was eluted with 1M pyridine and then evaporated, and the residue was dissolved in the mobile phase and subjected to high-performance liquid chromatography. The present method shortened the time needed to complete the assay by about 30min per sample and improved the separation of Nτ-methylhistidine.
