中文摘要：

研究药物分子在不同介质中引起的溶液体系的结构性改变有助于从分子水平揭示药物发挥疗效的机理.应用等温滴定微量热法测定了298.15K下头孢曲松钠在不同浓度氯化钠、氯化钾水溶液中的稀释焓,根据McMillan-Mayer理论计算得到各级同系焓相互作用系数.结果表明,头孢曲松钠在氯化钠、氯化钾水溶液中的焓对作用系数h2均为负值,并且随着盐溶液浓度的增加先减小后增加.该药物分子在氯化钾溶液中的h2大于氯化钠溶液.根据溶质-溶质相互作用和溶质-溶剂相互作用对结果进行了解释.

英文摘要：

The investigation of the structural change of solution systems caused by drug molecules in different media is helpful to elucidate the mechanism of playing curative effect of drug at the molecular level. The dilution enthalpies of ceftriaxone sodium in aqueous sodium chloride and potassium chloride solutions of different concentrations were measured by isothermal titration calorimetry at 298.15 K. The homogeneous enthalpic interaction coefficients were calculated according to the McMillan-Mayer theory. It is found that enthalpic pairwise interaction coefficients h2 of ceftriaxone sodium are all negative and pass through a minimum in aqueous sodium chloride and potassium chloride solutions. The value of h： in aqueous potassium chloride solutions is larger than that in aqueous sodium chloride solutions of the same molality. The results are discussed in terms of the solute-solute and solute-solvent interactions.