用静态平衡法测定了肝炎辅助治疗药物齐墩果酸在温度293.15～338.15 K、pH 7～10、醇浓度50％～90％的乙醇-水中的溶解度.溶解度随着pH值、醇浓度和温度的升高而增大,三者影响程度依次减弱.pH 8～10内,溶解度随pH升高快速增大;只在pH 9～10内,溶解度随醇浓度升高显著增大；只在pH 9～10与醇浓度80％～90％时,溶解度随温度升高缓慢增大.可见调酸反应结晶为齐墩果酸较适宜的结晶方式.当向λ-h方程中引入修正醇浓度和pH对溶解度影响的经验函数时,修正的λ-h方程可将80组溶解度数据满意关联,相关系数达到0.986,平均相对偏差为6.3％.借助激光监测法所测定的齐墩果酸在室温范围内于乙醇-水中反应结晶时的介稳区宽度与饱和浓度呈线性增长,线性相关系数高达0.998.%Oleanolic acid is a naturally occuring triterpenoid, widely used as an OTC drug for acute and chronic hepatitis. Its solubility in ethanol-water was measured at 293.15-338.15K, pH 7-10 and ethanol concentration 50%~90%. The solubility increases sharply with pH value from 8 to 10, rises with increasing ethanol concentration only during higher pH range (9-10) and increases slowly with the increase of temperature only during pH 9~10 and ethanol concentration of 80%~90%. pH, ethanol concentration and temperature show less and less effects on the solubility and hence the reaction crystallization by adjusting acidity is suitable for oleanolic acid purification. The famous λ-h equation were modified with two empirical functions to include the effects of pH value and ethanol concentration on the solubility, by which 80 groups of experimental solubility data were well correlated with a relative coefficient of 0.986 and an average error of 6.3%. The reaction crystallization metastable zone of oleanolic acid in ethanol-water under room temperature was determined by using laser monitoring technique. The metastable zone width increases linearly with increasing saturation concentration of oleanolic acid with a correlation coefficient up to 0.998.
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