| The silica-based phases are the most widely used materials in HPLC. Silica supports are superior to other supports in terms of efficiency, rigidity and performance. However, there are several disadvantages with silica-based materials such as severe peak tailing in the chromatogram of basic compounds and limited pH stability. The defects of silica limit its application in some important fields. The development of high-performance liquid chromatography (HPLC) as an efficient separation technique was always dependent on the synthesis of suitable packing materials. There has been an increasing importance in application of zirconia-based HPLC packings for their excellent chemical stability as well as bioanalysis suitability.The goal of this study is to prepare uniform zirconia-based support by LbL SA, which have both silica's and zirconia's virtues. Meanwhile the normal-phase, reversed-phase and chiral chromatographic performance were studied.The main research aspects are summaried as follows:1. Uniform and controlled silica micrometer particles were prepared by polymerization-induced colloid aggregation process. Important influence factors on the particle size, size distribution and mechanical strength were observed.2. Utilizing the LbL self-assembly method with low-cost ZrOCl2.8H2O as the raw material and SiO2 as core supports, obtained shell nano-structure ZrO2 composite successfully. The influence of times of assembling and assemble medium on the surface condition and content of ZrO2 were studied. The results show that ZrOCl2.8H2O concentrion of 0.25mol/L, assembly temperature 70℃, assembly layers 8 and calcine temperature 500℃are the best experimental conditions.3. The parameters of ZrO2/SiO2 core-shell composite were investigated. The above results prove that ZrO2/SiO2 is suitable for HPLC packing materials. The acidity ZrO2/SiO2 is lower than silica and the pH stability of ZrO2/SiO2 is superior to silica. Comparing with SiO2, the pH stability of ZrO2/SiO2 improved obviously. The novel support has the good chromatographic features such as larger surface area and pore volume, cylindraceous pore, more uniform particle size distribution.4. Amylose tris (3, 5-dimethylphenylcarbamate) coated zirconia (ADMPC coated ZrO2/SiO2) and the C18-ZrO2/SiO2 supports (ODZ) were prepared for high performance liquid chromatography. The two stationary phases have good chromatographic features, high efficiency and good selectivity for basic compounds and neutral compounds.
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