黄芩素固体分散体的制备及大鼠体内生物利用度

Preparation of baicalein solid dispersions and oral bioavailability in rats

目的:制备黄芩素-PVPK30固体分散体,考察其物相及大鼠体内生物利用度。方法:采用溶剂法制备黄芩素-PVPK30固体分散体;利用溶出度法、扫描电子显微镜、差示扫描量热、粉末X射线衍射、红外光谱等方法分析药物在载体中的存在状态;采用HPLC法测定大鼠血浆中药物浓度,与原料药比较,对黄芩素-PVPK30固体分散体进行大鼠体内生物利用度评价。结果:物相分析结果表明,当药物与载体比例为1:2时,固体分散体中黄芩素以非结晶态无定形存在,且与载体有氢键作用。大鼠体内血药浓度-时间曲线表明,与原料药相比,黄芩素固体分散体达峰时间(tmax)缩短,达峰浓度(cmax)提高,相对生物利用度为164。结论:采用溶剂法制备黄芩素-PVPK30固体分散体,黄芩素以无定形存在,其体外溶出速率和大鼠体内吸收均有显著性提高。

Aim： To prepare baicalein solid dispersions with PVP K30, and to investigate its phase identification and oral bioavailability in rats. Methods： Baicalein solid dispersions were prepared by the solvent method, and characterized by methods including dissolution, scanning electromicroscopy, differential scanning calorimetry, powder X-ray diffractometry, and infrared spectroscopy. Related samples obtained from in vitro release and the bioavailability assessment in rats were assayed by HPLC. Results： It was indicated that baicalein existed in the solid dispersions at amorphous form and that it possibly interacted with PVP K30 via hydrogen bond when the ratio of drug to the carrier was 1 ： 2. Baicalein plasma concentration versus time curve in rats showed that the solid dispersion approach was associated with a significant decrease in tmax and an evident increase in cmax compared to raw substance baicalein. Comparing to raw subatance baicalein, the relative bioavailability of baicalein in the sol- id dispersions was 164%. Conclusion： Baicalein existed amorphously in the baicalein-PVP K30 solid dispersions prepared by the solvent method, and in vitro release and the oral bioavailability of baicelein were significantly increased.