Preparation And Evaluation Of Surface Functionalized Silica Chromatographic Separation Materials

Chromatographic separation materials are the core of chromatographic technique and the foundation of the development of various chromatographic separation mode.The preparation of separation materials with novel structure and excellent properties has been one of the hot research field of chromatography.The stationary phases,which are spherical porous silica immobilized the different types of groups on the surface by chemical bonding,have been the leading packing materials of chromatographic separation.This research is based on the research background above,a variety of liquid chromatography separation materials were prepared,the main research contents are as follows:1.A novel 2-methylimidazolium-functionalized silica stationary phase was prepared and further used for hydrophilic interaction and anion-exchange mixed-mode chromatography.The stationary phase was characterized by elemental analysis and Fourier transform infrared spectroscopy.The chromatographic properties of this stationary phase were investigated by hydrophilic chromatography for the separation of nucleosides,nucleobases,water soluble vitamins,sulfonamides and saccharides,and ion chromatography for the separation of inorganic anions.The effect of acetonitrile content,salt concentration and p H values of the mobile phase on the retention of the stationary phases was also investigated.Compared with 1-methylimidazolium-functionalized silica stationary phase,this new stationary phase demonstrated similar or better separation selectivity.2.Three stationary phases,respectively,poly?1-vinylimidazole?immobilized silica stationary phase?Sil-PIm?,poly?acrylic acid?immobilized silica stationary phase?Sil-PAA?,and poly?1-vinylimidazole?and poly?acrylic acid?co-immobilized silica stationary phase?Sil-PIm-PAA?,were prepared by the surface radical chain-transfer reaction in the deep eutectic solvents?DESs?.These stationary phases were characterized by elemental analysis and Fourier transform infrared spectroscopy.Their hydrophilic chromatographic properties were investigated for separation of nucleosides,nucleobases,saccharides and amino acids.The retention changes of nucleosides and nucleobases on these stationary phases were investigated under different chromatographic conditions including acetonitrile content,salt concentration,p H of mobile phase and column temperature.The results indicated that DESs can be used as the reaction solvents for the preparation of polymeric silica stationary phases.3.A new method of the preparation of ZIF-8@SiO₂ core-shell microspheres with 2-methyl imidazole bonded silica as precursor was proposed.The materials was characterized by scanning electron microscopy,X ray diffraction,elemental analysis and Fourier transform infrared spectroscopy.The characterization results showed that ZIF-8 was successfully modified on the surface of SiO₂.However,its application needs to be further expanded.