Chromatographic separation of racemic praziquantel and its residual determination in perch by LC-MS/MS

An enantioselective depletion study of praziquantel (PZQ) in perch muscle was done using a simple, sensitive and specific liquid chromatography–tandem mass spectrometry (LC–MS/MS) method. Two cyclic polypeptides and two cyclic saccharide chromatographic columns were evaluated. The new hydroxypropyl β-cyclodextrin (HP-RSP) superficially porous particle (SPP) column produced the optimum separation and was selected for the study. Deuterium labeled PZQ-d11 was used as the internal standard. The method was linear over concentration ranges of 5.00–5.00×102μgL−1 (r2≥0.99) for (-)-R-PZQ and (+)-S-PZQ. The average recoveries of R-PZQ and S-PZQ at three spiked levels of 5.00, 50.00 and 5.00×102μgkg−1 ranged from 86.1% to 98.2%, and the intra-day and inter-day relative standard deviations were less than 5%. The decision limit (CCα) and detection capability (CCβ) of R-PZQ and S-PZQ in perch muscle matrices were all 1.0μgkg−1 and 5.0μgkg−1, respectively. The method was successfully applied in monitoring the depletion of praziquantel enantiomers in perch muscle following oral administration. The elimination rate of R-PZQ and S-PZQ in perch muscle tissue is equivalent. [Display omitted] •New chiral columns were used for the enantioseparation of praziquantel.•Praziquantel enantiomers could be analyzed in the reverse-phase mode by LC-MS/MS.•Elimination rate of R-praziquantel is similar to S-praziquantel in perch muscle.