目的:测定槲皮素在不同溶剂中的平衡溶解度和表观油水分配系数,为槲皮素的提取纯化及剂型设计提供依据。方法:采用高效液相色谱法测定槲皮素在9种溶剂中的平衡溶解度及表观油水分配系数,并计算槲皮素在水和正辛醇中达到溶解平衡的热力学参数。结果:槲皮素在水和正辛醇中的平衡溶解度随温度的升高而升高,在水和正辛醇中的溶解过程是吸热的(ΔsolH0〉0),并且是熵增加过程;槲皮素在丙酮中溶解度最大,为16.91 mg·m L-1,水中最小,为0.09μg·m L-1;常温下槲皮素的表观油水分配系数为29 813.46(lg P=4.47)。结论:槲皮素为水溶性较差的中等极性化合物,可考虑应用增溶辅料或通过制剂技术增大溶解度,以提高生物利用度。
Objective:To determine the equilibrium solubility of quercetin in different solvents,so as to provide a basis for extraction and dosage form design.Methods:A high performance liquid chromatography(HPLC) was established to detect the equilibrium solubility of quercetin in nine solvents and the apparent coefficient;and to calculate the thermodynamic parameters for quercetin reaching equilibrium solubility in the 1-octanol and water system.Results:The solubility of quercetin in water and 1-octanol increased with the increase of temperature.The process of dissolving in water and 1-octano was endothermic(ΔsolH0 0),meanwhile the entropy was increasing.The maximum solubility of quercetin was in acetone,being 16.91 mg·m L-1and the minimum in water,being 0.09 μg·m L-1.The apparent oil-water partition coefficient of quercetin at room temperature was 29 813.46(lg P = 4.47).Conclusion:Quercetin is a moderate-polar compound which has a poor water solubility and a good permeability.Therefore solubilizers and drug preparation technology can be considered to increase its equilibrium solubility in order to improve its bioavailability.