磺胺类药物水溶解度的测定与关联

Determination and correlation of aqueous solubilities for sulfonamides

采用平衡法测定了(298.15～333.15)K温度范围内磺胺嘧啶、磺胺二甲基嘧啶、磺胺二甲氧嘧啶、磺胺对甲氧嘧啶、磺胺间甲氧嘧啶和磺胺甲恶唑6种常见磺胺类药物在水中的溶解度数据,并运用λh方程进行了关联,确定了方程参数,总均方根偏差为0.26×10^(-6)。结果表明,实验范围内磺胺嘧啶、磺胺二甲基嘧啶、磺胺二甲氧嘧啶、磺胺对甲氧嘧啶、磺胺间甲氧嘧啶和磺胺甲恶唑6种常见磺胺类药物的水溶解度均较小,且分别随温度的升高而略有增加,计算值与实验值吻合较好。根据溶解过程热力学,由溶解度实验数据计算出6组磺胺类药物水溶液的超额焓H^E>0,表明其溶解为吸热过程。

Using a static equilibrium method, the solubilities of sulfadiazine, sulfamethazine, sulfadimethoxine, sulfamethoxydiazine, sulfamonomethoxine and sulfamethoxazole in water have been determined experimentally from （298. 15 to 333.15 ） K. The experimental data were correlated with λh equation, the constants of equations were obtained. The solubilities calculated by the model showed good agreement with experimental and literature data, and the total rms was 0. 26 ×10^-6. The experimental results showed that the solubilities of sulfadiazine, sulfamethazine, sulfadimethoxine, sulfamethoxydiazine, sulfamonomethoxine and sulfamethoxazole in water over the range of （298. 15 to 333.15 ） K were all very small, and increased slightly with the increase of the temperature among the temperature range investigated, respectively. Based on relationship between the parameter h in λh equation and excess enthalpies HE, the excess enthalpies for six systems were calculated using experimental data, and it was shown that sulfonamides dessolving in water was endothermic.