纳米晶纤维素组装的手性介孔材料及其对手性药物的分离

Chiral mesoporous materials assembled with nanocrystalline cellulose and its application in separation of chiral drugs

纤维素纳米晶体(CNC)是由硫酸催化的纤维素水解制备的,根据纤维素的来源和水解条件,纳米晶体的直径约为5~15 nm,长度约为100~300 nm。CNC在水中可以形成具有手性向列型结构的液晶相。当干燥成固体薄膜时,CNC保持螺旋手性向列顺序并组装成层状结构。在CNC自组装过程中,可以添加溶胶-凝胶前体,如Si(OMe)_(4)。随着溶剂的蒸发,这些前体会发生水解和缩合,从而形成手性向列相二氧化硅/CNC复合材料。复合材料在空气中煅烧破坏纤维素模板,留下高表面积手性向列结构的介孔二氧化硅膜。此外,有机二氧化硅或二氧化钛薄膜也采用类似的方法得到。这些薄膜可用作滤光片、反射器和薄膜。最重要的是,合成的手性介孔二氧化硅可用作手性色谱固定相材料分离手性药物。结果显示,手性分离的效果显著,为CNC开发手性新材料提供了新方法。

Cellulose nanocrystals(CNC)are prepared by hydrolysis of cellulose catalyzed by sulfuric acid.According to the source and hydrolysis conditions of cellulose,the diameter of the nanocrystals is about 5~15 nm and the length is about 100~300 nm.CNC organizes into chiral nematic liquid crystals in water.When dried into a thin solid film,the CNCs retain the helicoidal chiral nematic order and assemble into a layered structure.In the process of CNC self-assembly,it is possible to add sol-gel precursors,such as Si(OMe)_(4).With the evaporation of solvent,these precursors undergo hydrolysis and condensation,leading to a chiral nematic silica/CNC composite material.In addition,porous,rainbow colored organic silica or titanium dioxide films are also obtained using this methods.These thin films can be used as filters,reflectors,and membranes.The most important thing is that the synthesized chiral mesoporous silica can be used as a chiral chromatographic stationary phase material to separate chiral drugs.The results shows that the effect of chiral separation is remarkable,providing a new method for the development of chiral new materials based on CNC.