黄芩总黄酮溶解度和表观油水分配系数的测定

Determination of solubility and apparent oil/water partition coefficient of total flavonoids from Scutellaria baicalensis Georgi

目的:测定黄芩总黄酮的溶解度和表观油水分配系数,为指导其剂型设计和制备提供一些参考。方法:采用紫外分光光度法测定了黄芩总黄酮在水及不同溶剂的溶解度,同时测定了其在正辛醇-水/缓冲溶液中的表观油水分配系数。结果:黄芩总黄酮的溶解度随着溶剂极性的降低而降低,并且在碱性环境中的溶解度相对较高;黄芩总黄酮的表观油水分配系数与溶液pH有一定的关系,在pH2.0缓冲液中的表观油水分配系数最高,为15.874。结论:黄芩总黄酮的溶解性较差,而且pH对其溶解度和表观油水分配系数均有较大影响。

OBJECHVE To determine the solubility of total flavonoids from S. baicalensis and its apparent oil/water parti- tion coefficients; to provide the reference for its new formulations design and preparation. METHODS UV method was used to detect the concentration of total flavonoids from S. baicalensis in water and several frequently-used organic solvent, the appar- ent oil/water partition coefficients for n-caprylic alcohol water/buffer solution system were also explored. RESULTS Solubili- ty of total flavonoids from S. baicalensis exhibited such trends that decreased with the reduction of solvent polarity, and solu- bility in alkaline environment was higher. Meanwhile, apparent oil/water partition coefficients of total flavonoids from S. ba icalensis had a certain relationship with pH, and its value at pH 2. 0 was up to 15. 874, higher than that of other pH condi- tions. CONCLUSION Solubility of total flavonoids from S. baicalensis was poor in the aforementioned solvents. Its solubility and apparent oil/water partition coefficient were both highly concerned with pH.