The solubility of sulfamethazine (SMT) in ethylene glycol (EG) + water (W) cosolvent mixtures was determined at nine temperatures (278.15, 283.15, 288.15, 293.15, 298.15, 303.15, 308.15, 313.15 and 318.15 K) by means of the stirring method. From the solubility data, the thermodynamic functions of solution, transfer and mixing were calculated using the Gibbs and van´t Hoff equations. On the other hand, the preferential solvation parameters of SMT were determined by means of the method of the inverse integrals of Kirkwood-Buff (IKBI). In general terms, the solubility of SMT is favored by the increase in temperature and the decrease in the polarity of the cosolvent system, thus the maximum solubility is reached in pure EG at 318.15 K and the minimum in pure water at 278.15 K. Gibbs energy is positive in all cases, with a higher contribution from the energy component (enthalpy of solution). Regarding enthalpy-entropic compensation, the process is driven in all cases by the enthalpy of solution. Finally, SMT is preferentially solvated by water in mixtures with higher polarity and by EG in less polar mixtures.

通过搅拌在九个温度下（278.15、283.15、288.15、293.15、298.15、303.15、308.15、313.15和318.15 K）测定磺胺二甲嘧啶（SMT）在乙二醇（EG）+水（W）助溶剂混合物中的溶解度方法。根据溶解度数据，使用Gibbs和van´t Hoff方程计算溶液的热力学函数，传递函数和混合函数。另一方面，SMT的优先溶剂化参数是通过柯克伍德-布夫逆积分方法（IKBI）确定的。一般而言，温度升高和助溶剂体系极性降低有利于SMT的溶解度，因此，纯EG在318.15 K时达到最大溶解度，而纯水中在278.15 K时达到最小溶解度。吉布斯能量在所有情况下都是积极的，能量成分（溶液的焓）的贡献更大。关于焓-熵补偿，在所有情况下，过程都是由溶液的焓驱动的。最后，优先将SMT溶解在极性较高的混合物中的水和EG在极性较低的混合物中的溶剂。