以十八烷基三氯硅烷和3-巯丙基三甲氧基硅烷为改性剂,采用一锅法对硅胶表面加以修饰,进一步将巯基氧化制备成C18-磺酸基双改性液相色谱固定相。在优化的反应条件下得到了十八烷基和磺酸基摩尔比为3∶7的固定相,分别采用扫描电镜、元素分析、红外光谱对固定相的形貌和特征加以表征。针对制备的固定相,在不同的分离模式下,系统考察其色谱分离性能。在反相色谱模式下,成功分离了5种烷基苯化合物;在亲水模式下,分离了3种核苷;进一步应用于牛血清白蛋白酶解产物的分离,得到了较好的结果。实验结果表明,制备的混合模式固定相同时具有多种分离机理,在分离复杂样品、调整选择性方面具有潜在的优势。
A C18-sulfonic group dual modification chromatographic stationary phase was prepared by one-pot reaction to modify the surface of silica with two modifier of octadecyltrichlorosilane(OTS) and trimethoxysilylpropanethiol(MPS) and oxidize the thiol group.Under the optimized reaction conditions,the stationary phase with a mole ratio of 3 ∶ 7 between C18 and sulfonic group was obtained.The morphology and feature of the stationary phase were characterized by scanning electronic microscopy,elemental analysis and infrared spectra.The chromatographic properties of the prepared stationary phase were systematically investigated in different separation modes.Five alkyl benzenes and three nucleosides were separated successfully in reversed phase chromatography and hydrophilic interaction chromatography respectively.The bovine serum albumin digests could also be separated well on the stationary phase.The results indicated that the prepared mixed-mode stationary phase could provide multiple separation mechanism and had potential advantages in separating complex samples and adjusting the selectivity.