锆基色谱填料的制备方法和物理化学性质

氧化锆基质色谱填料适合于碱性物质，特别是生物大分子的分离,因而具有良好的应用前景。它的制备方法对其物理化学性质有很大的影响,从而影响填料的色谱性能。该文对氧化锆微球的制备方法及其物理化学性质进行了综述。分析表明，目前氧化锆基质色谱填料的制备方法存在着难以克服的缺点,要制备理想的锆基色谱填料需要新的思路。

Preparation and Physicochemical Properties for Zirconia as High Performance Liquid Chromatographic Packing Materials

There has been an increasing importance in the application of zirconia as column packing material for high performance liquid chromatography(HPLC)(because) of its excellent chemical,thermal,and mechanical stabilities as well as bioanalysis suitability.Zirconia spheres could be synthesized by polymerization-induced colloid aggregation(PICA),oil emulsion methods(OEM),or spray-dry method.It has been found that preparative procedure of zirconia support can affect its chromatographic behavior significantly.The review analyzes the relationship between zirconia packings' physicochemical properties and their preparative procedures.Specific surface area,pore structure,pore volume,pore size(distribution,) and particle size(distribution) are discussed in detail.At present, zirconia has not become highly competitive(because) of its limitations such as small specific surface area and pore volume,broad pore size(distribution) and particle(distribution),and unfavorable pore structure.The review also describes silica-zirconia composite HPLC materials prepared by sol-gel method, coating and co-precipitation procedure.However,their chemical stability as HPLC column packings was suspicious(because) of the residual silica on the material surface.Furthermore,the study showed that zircon(ZrSiO_4) is present in all silica-coated zirconia or silica-zirconia composites.It could be deduced that co-existence of more than one crystallines on the material surface could produce chemical heterogeneity,resulting in complex chromatographic separation mechanism.It leads a conclusion that a new synthetic way is needed for preparing zirconia-based HPLC packings with ideal chromatographic parameters.A novel material with higher specific surface area and pore volume,good pore structure, narrower pore size distribution and more uniform particle size distribution was prepared by layer-by-layer self-assembly technique(LbL SA),consisting of micrometer-sized silica spheres as core and nanometer-size zirconia particles as surface coating.The chemical stability of the material is as good as that of zirconia,and its specific surface area is as high as that of silica.