Salting-out-assisted liquid-liquid extraction with acetonitrile for the determination of trimetazidine in rat plasma using liquid chromatography-mass spectrometry.

A high-throughout bioanalytical method based on salting-out-assisted liquid/liquid extraction (SALLE) method with acetonitrile and mass spectrometry-compatible salts followed by LC-MS/MS analysis of trimetazidine in rat plasma is presented. It required only 50 μL of plasma and allows the use of minimal volumes of organic solvents. The seamless interface of SALLE and LC-MS eliminated the drying-down step and the extract was diluted and injected into an LC-MS/MS system with a cycle time of 2.5 min/sample. The retention times of trimetazidine and IS were approximately 1.1 and 1.7 min, respectively. Calibration curves were linear over the concentration range of 0.1-100 ng/mL, which can be extended to 500 ng/mL by dilution. The intra- and inter-batch precision, accuracy and the relative standard deviation were all <15%. This method was successfully applied to determine trimetazidine concentrations in rat plasma.