采用配位体金属离子交换剂作为手性流动相添加剂,以L-苯丙氨酸和硫酸铜溶液为手性配体流动相,考察了293~313K温度范围内,氧氟沙星对映体在C18高效液相色谱柱上拆分的热力学性质。结果表明,在实验范围内,随着温度的升高,对映体的保留时间、分离度和选择性因子均减少;用Ink’对1/T作图,得Van’t Hoff曲线具有良好的线性关系,相关系数R〉0.999。计算了氧氟沙星对映体在色谱柱分离的焓变、焓变差值和熵变差值等热力学参数。在实验温度范围内,氧氟沙星对映体满足|ΔS,RΔH^0|〉|TΔS,R ΔS^0|说明手性拆分过程为焓控过程。
Using ligand metal ion exchanger as chiral mobile phase additives , L-phenylalanine and copper sulfate solution as chiral ligand mobile phase, the thermodynamic properties of the resolution of ofloxacin enantiomers on C18 HPLC column was investigated at the temperature ranged from 293 to 313K. Experimental results showed that, in the experimental temperature range, the retention time, separation factor and selectivity of the enantiomers were reduced with the increasing temperature; plotting lnk' to 1/T got a Vanl Hoff curve with good linearity relations, of which the correlation coefficient R 〉 0. 999. The entbalpy change, enthalpy change difference, entropy change and other thermodynamic parameters of the separation of ofloxacin enantiomers on HPLC column were calculated. In theexperimental temperature range, the ofloxacin enantiomers met |ΔS,RΔH^0|〉|TΔS,R ΔS^0| to show that the process of chiral separation was an enthalpy-controlled process.