目的 测定盐酸氨溴索在多个pH值介质中的平衡溶解度及表观油水分配系数，为其制剂研究与处方筛选提供依据。方法 采用紫外分光光度法测定盐酸氨溴索在水及10种有机溶剂中的平衡溶解度，通过盐酸氨溴索分配平衡后在油相和水相中的浓度比，计算其油水分配系数。结果 盐酸氨溴索在各pH值介质中的平衡溶解度均较高，尤其是在蒸馏水以及pH值为2.0、5.8的缓冲液中，平衡溶解度分别为26.04、27.91、28.24 mg/mL；油水分配系数在pH7.4时最高，lgP为1.78。结论 盐酸氨溴索的平衡溶解度及表观油水分配系数与各介质的pH值有关，且可推测其在人体内的胃肠吸收良好，有较好的应用价值。

Objective To determine the equilibrium solubility of ambroxol hydrochloride and its apparent oil/ water partition coeffioients at different pH for the study of the preparations and formulation selection. Methods UV method was used to detect concentration of ambroxol hydrochloride in water and ten organic solvent, and K_O/W was calculated with concentration ratio of ambroxol hydrochloride in n-octanol and water phase after partition equilibrium. Results The equilibrium solubility of ambroxol hydrochloride is high in various solvents, especially at distilled water, pH 2.0 and pH 5.8, the equilibrium solubility are 26.04, 27.71, 28.24 mg/mL; And the maximum of apparent partition coefficient is 60.80 at pH 7.4. Conclusion The equilibrium solubility and apparent partition coefficient of ambroxol hydrochloride are correlated to pH of the medium. And it can be inferred that ambroxol hydrochloride can be absorbed by the gastrointestinal and has better using value.