新型亲水整体柱的制备及其在毛细管液相色谱和加压电色谱中的应用

以N,N-二甲基-N-甲基丙烯酰胺基丙基-N,N-二甲基-N-丙烷磺酸内盐(SPP)为单体,季戊四醇三丙烯酸酯(PETA)为交联剂,偶氮二异丁腈(AIBN)为引发剂及两类不同的致孔剂(乙醇/乙二醇和甲醇/1,4-丁二醇)制备了两种新型亲水性整体柱。为了获得理想的柱效、电渗流速度和渗透性,对制备整体柱的各反应物配比进行了研究和优化。比较了两种整体柱在渗透性和分离样品方面的性能,结果表明,以乙醇/乙二醇为致孔剂制备的整体柱在柱效、分离度方面优于以甲醇/1,4-丁二醇为致孔剂制备的整体柱,但在渗透性方面不及后者。探讨了流动相中盐浓度对核苷类样品保留的影响,发现当甲酸铵浓度从10 mmol/L增加到70 mmol/L时,核苷样品的保留因子呈现先增加后减小的状态。将制备的整体柱用于毛细管液相色谱和加压电色谱分别分离胺类、酚类和核苷类样品,获得了理想的分离效果。在分离酚类和核苷类混合样品时,发现加压毛细管电色谱在分离度和分离速度上均优于毛细管液相色谱。

Preparation of new hydrophilic monolithic columns and their applications in capillary liquid chromatography and pressurized capillary electrochromatography

New hydrophilic monolithic columns were prepared with {3-(methacryloylamino) propyl] dimethyl(3-sulfopropyl)ammonium hydroxide inner salt (SPP)} as monomer, pentaerythritol triacrylate (PETA) as crosslinking agent, azobisisobutyronitrile (AIBN) as initiator with two different porogens consisting of ethanol/ethylene glycol and methanol/1 ,4-butanediol, separately. In order to obtain monolithic columns with satisfactory efficiency, electroosmotic flow (EOF) velocity and permeability, the contents of the polymerization mixture were investigated and optimized. The performances of the two columns were compared in the permeability and separation performance. It was found that the monolithic column prepared with ethanol/ ethylene glycol had a better column efficiency and selectivity than that with methanol/1,4-butanediol, but was inferior to the latter in permeability. The effect of salt concentration (from 10 to 70 mmol/L ammonium formate) on the retention of nucleosides was investigated. It was observed that the retention factors of these nucleosides increased at first and then decreased. The columns were used in capillary liquid chromatography (cLC) and pressurized capillary electrochromatography (pCEC) for the separation of a test mixture of amines, phenols and nucleosides separately, and satisfactory separations for these samples were achieved. The column used in pCEC system showed better separation and higher speed of the mixture consisted of phenols and nucleosides compared to those used in cLC system.