木糖醇和麦芽糖醇型亲水作用色谱固定相的制备及其分离性能的评价

利用-NCO和-OH的加成反应,通过简单的两步反应将木糖醇和麦芽糖醇成功地键合于硅胶表面,制备了两种新型糖醇类亲水作用色谱固定相。流动相中乙腈含量对保留的影响曲线表明,这两种糖醇固定相具有典型的亲水作用色谱固定相性质,对极性和亲水性化合物有很强的保留作用。利用这两种固定相成功分离了水溶性维生素、水杨酸及其类似物、碱基及其相应的核苷和淫羊藿苷类似物等模型混合物,同时糖醇固定相展现了新颖的选择性,特别是相对于线形的木糖醇键合固定相,非线形的麦芽糖醇键合固定相表现出了对糖基的独特保留能力。此外,缓冲盐的pH和浓度对保留的影响表明静电作用在这两种糖醇固定相的保留机理中也发挥着一定的作用。本文所发展的糖醇类固定相具有良好的分离性能,有望在亲水作用色谱分离领域发挥潜在的应用价值。

Preparation of xylitol and maltitol modified silica as novel stationary phases for hydrophilic interaction liquid chromatography and evaluation of their separation performance

New types of stationary phases for hydrophilic interaction liquid chromatography (HILIC) with unique selectivity are very important for the separation of various polar and hydrophilic analytes. Two novel HILIC stationary phases based on sugar alcohol modified silica were synthesized by a simple two-step reaction in which xylitol and maltitol were bonded onto the surface of silica particles via the addition reaction between-NCO and-OH. The effect of acetonitrile content on the retention indicated that the two stationary phases were of typical HILIC character and exhibited strong retention for polar and hydrophilic analytes. They succeeded in the separation of a wide range of polar and hydrophilic analytes including water soluble vitamins, salicylic acid and its analogues, nucleic acid bases and nucleosides, and icariin and its analogues with unique selectivity. Especially, the maltitol stationary phase showed unique selectivity on glycosyl group, compared to xylitol stationary phase. Furthermore, the effects of buffer pH as well as salt concentration on the retention indicated that electrostatic interaction played an important role in the separation mechanism of the two stationary phases. For sure, the efficient stationary phases are of great potential applications in HILIC.