中文摘要：

目的：对磷酸川芎嗪的理化性质及生物学性质进行研究，为设计磷酸川芎嗪的不同剂型提供理论依据。方法：测定磷酸川芎嗪在不同温度及不同介质中的溶解度、表观油/水分配系数（P）、酸碱解离常数（pKa）、药物血浆蛋白结合率等体外理化性质及大鼠灌胃和静注磷酸川芎嗪水溶液后的药动学行为，以高效液相色谱法测定体外含量及血浆样品中磷酸川芎嗪的浓度。结果：磷酸川芎嗪属于易溶性药物；P值随pH升高呈S型变化；具有二级解离，pKa，=3．50，pKa2=6．86；血浆蛋白结合率为常数，大约为60％；在大鼠体内吸收快，代谢也快，绝对生物利用度较高。结论：磷酸川芎嗪在胃肠道吸收良好。溶解度高，基本属于生物药剂学分类系统（BCS）中Ⅰ类药物，但在体内代谢迅速。

英文摘要：

OBJECTIVE To study physicochemical and biological properties of tetramethylpyrazine phosphate （TMPP）. METHODS The physicochemical properties in vizro including solubility,oil/water partition coefficient （P） , dissociation constant （pKa）, the plasma protein binding ratio et al. and the pharmaceutical behaviors of TMPP solution after oral administration and intravenous injection in rats were determined. HPLC was used to determine the concentration level of TMPP in vitro sample and in plasma. RESULTS TMPP was soluble in water and the Po/w of TMPP changed in the shape of S with the increase of the pH. TMPP owned the property of two step dissociation with the pKa1 and pKa2 being 3.5 and 6.86, respectively. The mean plasma protein binding ratio of TMPP was a constant, about 60%. The rates of both the absorption and metabolism of TMPP in rats were fast as well as the resolute bioavailability was high. CONCLUSION TMPP had a good absorption in gastrointestinal （GI）, a high solubility but a relatively fast rate of metabolism in vivo, which on the whole belonged to the class Ⅰ of Biopharmaceutical Classification System （BCS）.