Detection of doping peptides and basic drugs in equine urine using liquid chromatography –mass spectrometry

This study describes the development and validation of methodology capable of the detection of over 50 different peptide-based doping agents, related secretagogues, quaternary ammoniu m drugs, and other challenging small molecules in equine urine following solid-phase extraction using a mixed mode weak cation exchange sorbent. Following sample extraction, the compounds were analyzed using LC–MS with chromatographic separation via a reverse phase gradient and detection via selec tive reaction monitoring following introduction to a triple-stage quadrupole mass spectrometer using positive mode electrospray ionization. Validation parameters including limits of detection and quantitation, accuracy, precision, linear range, recovery, stability, and matrix effects were determined . Briefly, the limits of detection for most compounds were in the sub-ng/mL ranges with adequate precision and accuracy sufficient for an initial testing procedure. Stability studies indicated that most compounds were sufficiently stable to allow for effective screening using conditions commonly uti lized in drug testing laboratories.
Source: Drug Testing and Analysis - Category: Drugs & Pharmacology Authors: Tags: RESEARCH ARTICLE Source Type: research