Development of novel organic phases for high selective and sensitive HPLC by controlled surface modification

本研究旨在开发一类具有高选择性的新型高效液相色谱填料。为了实现这一目的，我们提出了两个目标：（1）表面形态的物理控制和（2）通过接枝聚合对支撑材料和HPLC应用进行化学修饰。我们建立了一种新的方法来创建核壳粒子与二氧化硅粒子层壳。该方法具有几个优点，可以强调如下：（a）核-壳颗粒可以容易地通过一锅悬浮聚合制备。(b)所得壳通过共价键合稳定地固定。(c)通过合理选择二氧化硅粒子的粒径和组合，可以将壳层结构从单层调整到多层。(d)通过使用多孔二氧化硅颗粒和去除二氧化硅颗粒，可以产生凹坑结构表面.对于二氧化硅表面的化学功能化，聚合物接枝方法进行了研究。使用具有杂环结构的乙烯基单体，例如咔唑和恶唑。所得杂化物在高效液相色谱中表现出优异的分离能力，尤其是对多环芳烃的分离。它也已经建立，选择性可以调整，不仅通过选择一种单体，但也聚合方法。在基线分离含有β-和γ-异构体的生育酚中观察到最成功的结果。

This research project aims to develop a new class of HPLC packing materials with high selectivity. To accomplish this purpose, we proposed two goals :(1) Physical control of surface morphology and (2) chemical modification by graft polymerization on supporting materials and HPLC applications.1. We established a new method for creation of core-shell particles with silica particles-layer shells. This method has several advantages that can be emphasized as follows :(a) the core-shell particles can be readily prepared by one-pot suspension polymerization.(b) The resultant shell is stably immobilized by covalent bonding.(c) By proper choosing the diameter and combination of silica particles, the shell structures can be adjusted from single-to multi-layers.(d) By using porous silica particles and removal of silica particles, the dimple structural surface can be created.2. For chemical functionalization of silica surface, a polymer-grafting method has been investigated. Vinyl monomers with heterocyclic structures such as carbazole and oxazole were used. The resultant hybrids showed excellent separation ability in HPLC especially for polyaromatic hydrocarbons. It has also been established that the selectivity can be tuned by not only choosing a monomer but also polymerization method. The most successful results were observed in the base-line separation of tocopheroles containing β- and γisomers.