Determination of eleutheroside E and eleutheroside B in rat plasma and tissue by high-performance liquid chromatography using solid-phase extraction and photodiode array detection

A HPLC method with photodiode array detection (PDA) was developed for the determination and a pharmacokinetic study of eleutheroside E (ELU E) and eleutheroside B (ELU B) in rat plasma Laid tissue following an eleutherococcus injection. The analysis was performed on a Kromasil C-18 column, using water-acetonitrile as the gradient mobile phase and 0.8 rL/min flow rate. Detection wavelengths of ELU E and ELU B were 220 and 206 nm, respectively. Protein from the biological sample was deposited using acetonitrile. ELU E and ELU B were extracted from the biological samples using acetonitrile, separated by solid-phase extraction, and eluted from the cartridge using 60% methanol. The extraction recovery of ELU E and ELU B was 91.2 and 88.8%, respectively. The limit of detection was 37.6 ng/mL for ELU E and 37.0 ng/mL for ELU B (S/N=3) in plasma. Blood drug level-time cuvers of ELU E and ELU B in Wister rats following administration of an eleutherococcus injection into femoral vein were shown to fit a three-compartment model. The half-life (t(1/2)) was 4.662 h for ELU E and 2.494 h for ELU B. Following administration of a single eleutherococcus injection, the concentration of ELU E and ELU B in the tissue was C-liver> C-kidney> C-spleen> C-heart and C-kidney> C-liver> C-heart. We believe the method described in the present paper is accurate and reliable and can be used for pharmacokinetic Studies of ELU E and ELU B in rats. In addition, the method for sample preparation, using solid phase extraction, is precise, simple and rapid. (c) 2005 Elsevier B.V. All rights reserved.