Determination of deoxyschizandrin in rat plasma by LC-MS

A simple, rapid and sensitive LC-MS method was developed for quantification of deoxyschizandrin in rat plasma. A 50 PI plasma sample was extracted by ether and performed on Elite Hypersil C-18 column (200 mm x 4.6 mm, 5 mu m) with the mobile phase of methanol-water (84:16, v/v) in a run time of 6.5 min. The analyte was monitored with positive atmospheric pressure chemical ionization (APCI) by selected ion monitoring (SIM) mode. A good linear relationship was obtained over the range of 1.0-50.0 ng/ml and the validated method was successfully applied for the pharmacokinetic studies of deoxyschizandrin in rat. After oral administration of 4 mg/kg deoxyschizandrin and Schisandra extract which contained the same dose of deoxyschizandrin to male rats, the C-max of deoxyschizandrin were 15.8 +/- 3.1 and 34.3 +/- 16.8 ng/ml, T,,m were 0.51 +/- 0.13 and 3.83 +/- 1.83 h, T-1/2 were 5.3 +/- 2.2 and 6.5 +/- 3.4 h. (c) 2007 Elsevier B.V. All rights reserved.