Study On The Preparation Of Chiral Open-tubular Columns With Zeolite Nanoparticles And Enantioseparation Methods Based On Capillary Electrochromatography

1.PrefaceCapillary electrochromatography（CEC）combines the advantages of chromatographic and electrophoretic separation,which has received a great deal of attention in the field of enantioseparation.In this chapter,the development history and separation principle of CEC are briefly introduced,and its recent research progresses in the preparation of chiral stationary phase materials and open-tubular（OT）columns are reviewed in detail.In this dissertation,the novel OT columns prepared by different chiral stationary phase construction strategies were applied to CEC with amperometric detection system（CEC-AD）to carry out the separation of chiral drugs and actual sample analysis.2.Study on the preparation of OT column with zeolite Si O₂NPs modified by dual chiral selectors as chiral stationary phase and its separation performance based on CEC-AD systemIn this work,a new type of chiral OT column using zeolite Si O₂NPs modified byβ-cyclodextrin and L-phenylalanine as chiral stationary phase was developed with the strong adhesion of polydopamine by one-step method.The effects of the total amount and proportion of two chiral selectors on the separation performance of OT column were investigated.The morphology and chemical properties of the OT columns were characterized by scanning electron microscopy and electroosmotic flow experiments,respectively.Enantioseparation of salbutamol and ritodrine racemes could be achieved by CEC-AD system.The run-to-run,day-to-day,and column-to-column stability of the prepared OT columns were evaluated using salbutamol raceme as the chiral model molecules,and the RSD values were within 8.9%.Under optimized electrophoretic conditions,the detection limits of salbutamol raceme were 0.90μg·m L^-1（S/N=3）.This method has been preliminarily used to analyze real sample.3.Study on the preparation of OT column with zeolite beta nanoparticles as chiral stationary phase and its separation performance based on miniaturized CEC-AD systemIn this work,a novel type of chiral OT column was prepared using zeolite beta nanoparticles as chiral stationary phase due to its enantioselectivity and size selectivity.The morphology and structure of zeolite beta nanoparticles were characterized by scanning electron microscopy and X-ray diffraction,respectively.The successful preparation of OT column was confirmed by scanning electron microscopy and electroosmotic flow experiments.The separation performance of the prepared OT columns was further evaluated by miniaturized CEC-AD system.Under optimized electrophoretic conditions,baseline separation of six pairs of chiral drugs could be achieved.The run-to-run,day-to-day and column-to-column reproducibility of the OT columns were evaluated using norepinephrine raceme as the model molecules,and the RSDs were within 8.7%.The detection limits of norepinephrine raceme were 0.15μg·m L^-1（S/N=3）.This developed method has been preliminarily applied to the determination of impurity enantiomer in the potassium dichromate norepinephrine injection samples.