胡椒碱平衡溶解度和表观油水分配系数的测定

Determination of equilibrium solubility and apparent oil/water partition coefficient of piperine

测定胡椒碱的平衡溶解度及表观油水分配系数,研究pH值对其影响,为胡椒碱在体内吸收研究提供参考.采用HPLC法测定了胡椒碱在水和5种有机溶剂中的平衡溶解质量浓度,并用摇瓶法测定胡椒碱在不同pH条件下的正辛醇-水缓冲溶液中的表观油水分配系数.结果表明:25℃下胡椒碱在水中的平衡溶解质量浓度为22.34 mg/L,而在有机溶剂中的溶解质量浓度较好,特别是在二氯甲烷中,其平衡溶解质量浓度高达43 665.5 mg/L,正辛醇∶水的表观油水分配系数P为179.33(lgP=2.25).

This study aimed to investigate the equilibrium solubility of piperine and its partition coefficient in the n-octanol-water/buffer solution systems, which could provide scientific information for the studies of its in vivo absorption. The concentrations of piperine in water and five organic solvents were determined by HPLC analysis,and the partition coefficients were calculated by the peak area. The results showed that the equilibrium solubility of piperine was 22.34 mg/L in water at 25 ℃. A higher equilibrum solubility was observed at 43 665.5 mg/L in dichloromethane, while the partition coefficient of piperine in the n-octanol-water：buffer solution systems was found at 179. 33 （ lgP = 2. 25 ）.