[Pharmacokinetics of oxymatrine and its metabolite in beagle dogs by LC-MS].
OBJECTIVE
To establish LC-MS method in the determination of oxymatrine and its metabolite in plasma and investigate their pharmacokinetics in beagle dogs.


METHODS
Lichrospher C18 column (4.6 mm x 250 mm, 5 microm) was used as the analytical column maintained at 25 degrees C. The mobile phase consisted of 10 mmol x L(-1) CH3COONH4 and CH3OH (25:75). Flow rate was 1 mL x min(-1). Electrospray ionization (ESI) was carried out. The ESI ion source was set in positive ion polasity mode. The selective ion monitoring (SIM) was set at m/z 265.1 and 249.2.


RESULTS
The linearity ranged from 2 to 5000 ng x mL(-1) (r = 0.9991). The detection of oxymatrine and its metabolite were 0.6 and 0.3 ng x mL(-1). The RSD(%) within day and between day was less than 4.7%. The recovery of this method was more than 96.5%. The disposition was conformed to a two-compartment model. The T(1/2), Tmax, Cmax, MRT, AUC(0-->24 h) of oxymatrine were (5.5+/-1.58) h, (1.0+/-0.30) h, (2418.3 +/-970.78) ng x mL(-1), (3.2+/-0.64) h, (5797.4+/-908.16) ng x mL(-1) x h accordingly. The corresponding T(1/2), Tmax, Cmax, MRT, AUC(0-->24 h) of matrine were (9.8+/-2.77) h, (1.9+/-1.09) h, (1532.4+/-494.86) ng x mL(-1), (4.4+/-1.97) h, (5530.5+/-1042.65) ng x mL(-1) x h.


CONCLUSIONS
This assay was highly sensitive, rapid, simple and specific enough for determining concentrations of oxymatrine and its metabolite matrine in plasma of beagle dog.
Wang
Su-jun
SJ
Center of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing 210038, China.
Wang
Guang-ji
GJ
Li
Xiao-tian
XT
Ma
Ren-ling
RL
Sun
Jian-guo
JG
Sheng
Long-sheng
LS
D000284:Administration, Oral; D000470:Alkaloids / Q000097:blood / Q000302:isolation & purification / Q000493:pharmacokinetics*; D000818:Animals; D019540:Area Under Curve; D002853:Chromatography, Liquid; D004285:Dogs; D008297:Male; D010946:Plants, Medicinal / Q000737:chemistry; D011807:Quinolizines; D029909:Sophora / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D000093842:Matrines
D000470:Alkaloids; D011807:Quinolizines; C037573:oxymatrine; D000093842:Matrines