| Monolithic column for capillary electrochromatography (CEC) was regarded as the novel generation of chromatography sorbents, which have attracted considerable attention in micro-separation field. The in situ preparation of monoliths offer the stationary phase with unique pore structure for high permeability and favourable mass transfer characteristics. This avoids the problems related to both frit fabrication and packing and simplify column technology. Both organic polymer and silica-based monoliths have been introduced to CEC. However, one critical drawback associated with polymer monoliths is its tendency to swell during exposure to various solvents in the running buffer. The size of silica skeletons and through pores of the silica-based monolithic columns can be controlled independently via the sol-gel process. The sol-gel network offers high permeability, high mechanical strength, high efficiency and good solvent resistance. However, the facture procedure is very complicated and only several groups have mastered this technique. In this thesis, the preparation of new type monolithic silica column were studied, and their electrochromatographic behavior have been investigated. Main points of this thesis are listed as following:1. The factors affecting the structure of silica monoliths were studied, including the reactant ratio, organic hybrid solvent, etc. Parameters affecting mesopore structures. New idea was presented and the sol-gel method reported in literatures was improved in this thesis.2. Monolithic silica column with mixed-modes of reversed-phase and anion-exchange stationary phases was proposed for pressurized capillary electrochromatography (pCEC) by a sol-gel process. The ammonium groups on the surface of the stationary phase generate an EOF from cathode to anode, and serve as a strong anion-exchange stationary at the same time.3. The amino bonded-silica monolithic columns with mixed mode of...
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