Ultra‐performance liquid‐chromatography with tandem mass spectrometry for rapid analysis of pharmacokinetics, biodistribution and excretion of schisandrin after oral administration of Shengmaisan

This study aimed to investigate the in vivo behaviors of the main components in traditional Chinese medicine (TCM) fomulae. The plasma pharmacokinetics, tissue distribution and excretion of the main component-schisandrin in rats after oral administration of a classical TCM prescription, shengmaisan (SMS), were studied by a developed and validated UPLC-MS/MS method. The separation of schisandrin was achieved on a UPLC HSS T3 column with a mobile phase consisting of acetonitrile and water at a flow rate of 0.5 mL/min by linear gradient elution. The MS/MS detection was carried out by monitoring the fragmentation of m/z 415.22 → 384.26 for schisandrin on a triple quadrupole mass spectrometer. The result showed that the method was suitable for the quantification of schisandrin in plasma, tissue and excreta samples with satisfactory selectivity, precision, accuracy, sensitivity, linearity and recovery. Pharmacokinetic results showed a rapid absorption phase with the mean Tmax of 0.17 h and a relatively slow elimination proceeding with a half-life (T1/2 ) of 5.24 ± 1.28 h. The tissue distribution showed the maximum concentration distributions of schisandrin after oral administration of SMS were in the order of small intestine > large intestine > lung > liver > kidney > spleen > heart > brain. Only 0.005-0.006% of schisandrin was recovered in feces and was not detected in urine.