Rapid liquid chromatography tandem mass spectrometry determination of rivaroxaban levels in human plasma for therapeutic drug monitoring

A rapid, sensitive, high-throughput liquid chromatography coupled with tandem mass spectrometry method for the quantification of rivaroxaban from human plasma has been developed and validated. For the analytical separation a Zorbax SB-C18 column with isocratic flow of mobile phase composed of 0.2% formic acid in water and acetonitril (65:35, V/V) with a flow rate of 1 mL/min at a temperature of 45ºC was used. Detection of rivaroxaban was performed using positive electrospray ionization and MS/MS mode (sum of m/z 231.1; 289.2 and 318.2 from m/z 436.3). Plasma samples were prepared using single-step protein precipitation with methanol. Method validation was performed with regards to selectivity, linearity (r >0.9927), within-run and between-run precision (CV< 13.1 %) and accuracy (bias< 9.4 %) over a concentration range of 24.00 - 960.00 ng/mL plasma. Recovery was between 96.5 - 108.5% and the lower limit of quantification of rivaroxaban was 24.00 ng/mL. The developed method is simple, rapid, and selective, requires small plasma sample volumes, and was successfully applied for therapeutic drug monitoring of rivaroxaban in treated patients.