Detection and quantification of dermorphin and selected analogs in equine urine

Background: Dermorphin, a hepta-peptide with potent analgesic properties, is classified as a doping agent in equine racing. Since its discovery, a number of biologically active structural analogs have been synthesized and made commercially available so there is a need for reliable methods of detection. Methodology/Results: A sensitive detection method was developed for dermorphin and six analogs in equine urine. Peptide enrichment was achieved using weak cation exchange with subsequent separation and detection by nano-UHPLC–MS/MS. Method validation parameters included: specificity, linearity (5–10000 pg/ml), recovery (58–93%), intra and inter-assay repeatability, LOD (5–50 pg/ml) and matrix effects. Conclusion: The presented method will facilitate...