反相离子对色谱中有机溶剂浓度和离子对试剂浓度对保留值的影响

Comparison of Aromatic Sulphonic Acids in Reversed-phase Ion-pair Liquid Chromatography with Different Organic Modifier and Ion-pair Reagent Concentration

我们测定了氨基苯磺酸和氨基萘磺酸在反相离子对色谱中不同乙腈/水、甲醇/水配比和离子对试剂浓度下的保留值,并把两种冲洗剂下的保留值和关系式lnk′=a+Cc_b中的参数a,C作线性关联,得到很好的相关性;这表明有机溶剂乙腈和甲醇对选择性并无显著的影响,但乙腈有更大的冲洗强度.证明关系式ink′=A+Blnc_p+Cc_b能较好地描述有机溶剂和离子对试剂浓度对保留值的影响,但当离子对试剂浓度较高时该关系式不成立.同时提出了有机溶剂浓度和离子对试剂浓度“等同效应”的概念.

The capacity factors of 15 aromatic sulphonic acids in reversed-phase ion-pair liquid chromatography (RP-IPC) with acetonitrile / water and methanol / water containing ion-pair reagent tetrabutylammonium iodide were measured, the linear regression between the Ink' values and methanol, acetonitrile concentrations according to equation Ink' = a+Ccb was carried out, good linear relationships of the Ink' values, the parameters a and C with acetonitrile as organic modifier vs. those with methanol as organic modifier were obtained, which mean that there is no significant difference in acetonitrile and methanol affecting the selectivity, the acetonitrile has a stronger eluent strength than methanol. The combined effect of organic modifier and ion-pair reagent concentration on retention values can be expressed by the equation Ink' = A+B In cp+Ccb in a suitable range of ion-pair reagent concentration. A critical value the positive effect of ion-pair reagent concentration on retention is equal to the negative effect of organic modifier concentration on retention has been obtained.