Chromatographic Performance Of TpBD-COF Modified Open Tubular Capillary Column In CEC And Its Application In Enantioseparation

Due to their specific topology,diverse cell composition,tunable pore properties,and flexible functional development,covalent organic frameworks（COFs）have showed great value in various fields including gas storage,heterogeneous catalysis,sensing,drug delivery,and energy storage.Moreover,because of the unique properties such as easy to modify,low density,large specific surface area,and good stability,COFs also have showed great potentiality in the field of separation science.Up to date,COFs have been applied in solid phase extraction（SPE）,solid-phase microextraction（SPME）,high performance liquid chromatography（HPLC）,gas chromatography（GC）,and capillary electrochromatography（CEC）.However,COFs have not been reported for the separation of chiral drugs in CEC.In this thesis,TpBD-COF modified open-tubular capillary column was prepared,and evaluated in CEC for its separation performance and the enantioseparation of several chiral drugs.The thesis includes four chapters:In Chapter 1,the basic concepts of CEC,covalent organic frameworks and their applications in the field of chromatographic separation were reviewed.In Chapter 2,TpBD-COF modified open tubular capillary column was prepared at higher temperatures by using 1,3,5-triformylphloroglucinol（Tp）and benzidine（BD）as the reaction monomers,and ethyl acetate（EA）as the solvent.The obtained open tubular capillary column was characterized by X-ray powder diffraction（XRD）,scanning electron microscope（SEM）,and infrared spectroscopy（IR）.Five alkylbenzenes including benzene,toluene,ethylbenzene,propylbenzene,and butylbenzene were used as tested analytes to evaluate the separation performance of TpBD-COF modified open tubular capillary column in CEC.To obtain the best separation,the thickness of the TpBD-COF layer,the concentration and pH of the borate buffer,and the content of the organic additive in the running buffer were optimized in CEC.The results showed that all of the five alkylbenzenes could be baseline separated on the TpBD-COF modified capillary column under the optimized conditions.In Chapter 3,based on the previous works,TpBD-COF modified open tubular capillary column was applied to the enantioseparation of four weakly basic drugs（lomefloxacin,gatifloxacin,dioxazine,and carvedilol）using L-sorbose–boric acid complex as the chiral selector in CEC.In order to obtain the best enantioseparation,the effects of the concentrations of L-sorbose,boric acid,and triethylamine were investigated.The results showed that compared with the previous work,all of the four chiral drugs could achieve better resolution under the optimized conditions in CEC.The feasibility of the developed method was tested for the determination of dioxazine enantiomers from tablets under the above optimized conditions in CEC.Good linearity was obtained in a range of 10μg·ml^-1500μg·ml^-11 for each dioxazine enantiomer and the recoveries for them were ranged from 96.3%to 105.0%with the relative standard deviation（RSD）less than 2.6%.The method is simple,rapid and reproducible,which can be used to determine the content of dioxazine enantiomers in tablets.In Chapter 4,conclusions and prospects were made.