[Simultaneous determination of four anthraquinones in rat plasma by HPLC-FLD method and its pharmacokinetic study].

This paper aims to develop a method for the determination of aloe-emodin, rhein, chrysophanol and physcion and study the pharmacokinetic properties of four anthraquinones in rat plasma after oral administration of gardenia and rhubarb decoction. The plasma concentrations at different time points of four anthraquinones were determined by HPLC-FLD method. Plasma samples were extracted with liquid-liquid extraction procedure. Plasma samples were separated on a C18 column (4.6 mm x 150 mm, 5 μm), using 0.2% acetic acid and methanol as mobile phase at a flow rate of 1.0 mL min(-1) with gradient elution. The excitation and emission wavelengths were set at 430, 525 nm, respectively. DAS 2.0 software was applied to calculate the pharmacokinetic parameters. The results showed four anthraquinones can be absorbed. The main parameters of aloe-emodin, rhein, chrysophanol and physcion were as follows: C(max) for aloe-emodin was (0.085 ± 0.058), (3.772 ± 1.152), (0.464 ± 0.267), (0.028 ± 0.008) mg x L(-1) respectively; t(max) for rhein was (1.042 ± 0.510), (0.805 ± 0.307), (1.167 ± 0.283), (0.616 ± 0.162) h respectively; t½ for chrysophanol was (3.557 ± 1.250), (6.879 ± 1.126), (5.196 ± 2.032), (4.337 ± 1.816) h; AUC(0-t) for physcion was (0.504 ± 0.130), (9.558 ± 1.106), (2.545 ± 1.554), (0.052 ± 0.018) mg x h x L(-1). This paper developed a selective, accurate and sensitive HPLC-FLD method for the simultaneous determination of four anthraquiones in rat plasma.