提出了洛美沙星对映体的高效液相色谱拆分方法。选用Chiralcel OJ手性柱,正己烷-异丁醇(90+10)的混合溶液为流动相,流量为0.6 mL·min-1,柱温为30 ℃,检测波长为287 nm。通过溶质计量置换保留模型和热力学理论对Chiralcel OJ手性柱拆分机理进行了探讨。结果表明:保留时间较短的洛美沙星对映体的lgI值和Z值均小于保留时间较长的对映体。在试验的温度范围内,用lnα对1/T作图,得到Van′t Hoff曲线呈线性关系,焓变和熵变之差为负值,说明手性拆分过程为焓控过程。

Resolution of enantiomers of lomefloxacin by HPLC was proposed using the Chiralcel OJ column as stationary phase with column temperature of 30 ℃, and a mixture of n-hexane and iso-butanol (90+10) as mobile phase with a flow-rate of 0.6 mL·min-1. UV-detection at the wavelength of 287 nm was adopted in the determination. Based on the solute stoichiometric displacement model of retention and the thermodynamic theory, mechanism of resolution of enantiomers of lomefloxacin on this chiral column was studied. It was found that values of lgI and Z of the enantiomer with shorter retention time were smaller than that of the enantiomer with longer retention time. Good linearity of the Van′t Hoff curve was obtained when plotting lnα vs. 1/T, within the testing temperature range; and the difference between enthalpy change and entropy change was shown to be a negative value. It was thus illustrated that the chiral resolution of the enantiomers was an enthalpy-controlled process.