5,7,3',4',5'-五甲氧基黄酮平衡溶解度及油水分配系数的测定

Determination of equilibrium solubility and apparent oil-water partition coefficient of 5,7,3',4',5'-pentamethoxyflavone

目的考察5,7,3',4',5'-五甲氧基黄酮在水和缓冲溶液中的平衡溶解度及表观油水分配系数。方法采用HPLC法测定5,7,3',4',5'-五甲氧基黄酮在不同介质中的平衡溶解度,摇瓶法测定表观油水分配系数。结果在37℃下,5,7,3',4',5'-五甲氧基黄酮及龙须藤总黄酮中的5,7,3',4',5'-五甲氧基黄酮在水中的平衡溶解度分别为0.603、77.702μg/mL,相应的表观油水分配系数为246.24(lg Papp=2.39)、257.51(lg Papp=2.41)。结论 5,7,3',4',5'-五甲氧基黄酮水溶性极差,脂溶性适中。与单体相比,龙须藤总黄酮中的5,7,3',4',5'-五甲氧基黄酮水溶性增大。

Objective To determine the equilibrium solubility and apparent oil-water partition coefficients of 5,7,3′,4′,5′-pentamethoxyflavone（ PMFA） and total flavonoids from Bauhinia championii in different p H phosphate buffer solutions. Methods A high performance liquid chromatography method was established to determine the concentrations in water and different p H phosphate buffer solution of PMFA and total flavonoids, while the oil-water partition coefficient for the n-octanol-water/buffer solution system was determined by shaking flask method. Results The equilibrium solubility of PMFA and total flavonoids were 0.603 μg/mL and 77.702 μg/mL in water at 37 ℃. The oil-water partition coefficient of PMFA and total flavonoids were 246.24（ lg Papp= 2.39） and 257.51（ lg Papp= 2.41）,respectively. Conclusion PMFA was not soluble in water,and had moderate lipid solubility. The solubility of PMFA increased in total flavonoids.