Retention slectivity achiebed by the stationary phase modified with mucoplysaccharides in liquid chromatography

用离子色谱法研究了粘多糖和葡聚糖硫酸盐修饰的硅胶阴离子交换剂对分析物离子的保留行为。改性显著降低了底物的阴离子交换容量，但诱导了阳离子交换性能。修饰后的固定相既具有底物的残留阴离子交换中心，又具有由于修饰剂的自由阴离子基团而产生的阳离子交换中心。底物的孔径和改性剂的相对分子质量对分析离子的保留行为有很大的影响。由于阴离子和阳离子都保留在改性固定相上，洗脱液中的阳离子和阴离子影响了分析离子的保留行为。在合适的条件下，阴离子和阳离子同时在修饰的固定相上分离。以肝素修饰的阴离子交换剂为固定相，研究了氯喹和其他胺衍生物的对映体分离。修饰和流动相条件影响分析物的分离。以含乙腈的缓冲溶液为流动相，可实现氯喹对映体的分离。

Retention behavior of analyte ions on silica-based anion exchangers modified with anionic polysaccharides such as mucopolysaccharides and dextran sulfate has been investisated in ion chromatography. The anion-exchange capacity of the substrate was remarkably reduced by the modification, whereas cation-exchange properties were induced. The modified stationary phases possess residual anion-exchange sites of the substrate as well as cation-exchange sites due to free anionic groups of the modifier. The pore size of the substrate and the molecular weight of the modifier strongly affected the retention behavior of analyte ions. Since both anions and cations were retained on the modified stationary phase, the cation and the anion of the eluent affected the retention behavior of analyte ions. Under appropriate conditions both anions and cations were simultaneously separated on the modified stationary phase.Enantiomeric separation of chloroquine and other amine derivatives has been investigated by liquid chromatography using anion-exchangers modifiled with heparin as the stationary phase. Modification and mobile phase conditions affected the separation of analytes. Separation of chloroquine enantiomers could be achieved by using buffer solution containing acetonitrile as the mobile phase.