Preparation Of Novel Polymethacrylate Capillary Monolithic Column And Its Application In Pressurized Capillary Electrochromatography

Capillary monolithic column was prepared by organic or inorganic insitu polymerization with a monolithic chromatography stationary phase.It has been a hotspot in recent years and known as the fourth generation separation phase because of its easy preparation,good permeability,no frit effect and simple modification of many functionalities.Polymethacrylate monolithic column is one of the most widely used polymer monolithic columns with a rich family of selective monomers and crosslikers,in which butyl methacrylate and glycidyl methacrylate were frequently-used monomers.The incorporation of nano-particles into polymer monolith is another research hotspot in recent years.The incorporation of nanomaterials enhances column efficiency and selectivity of the he monolithic column due to high specific surface area.This thesis is divided into five chapters:In the first chapter,the theory of capillary electrochromatography,pressurized capillary electrochromatography,monolithic column and nano-particle incorporated monolithic columnwas introducedin details.In the second chapter,the preparation,optimization and application of poly(BMA-EDMA-AMPS)monolithic column was introduced.The monolithic column was prepared by in-suit polymerization of butyl methacrylate(BMA),2-acrylamide-2-methylpropane sulfonic acid(AMPS)and ethylene glycol dimethacrylate(EDMA)as monomers and 1,4-butanediol,1-propanol,water as ternary porogens.The optimized fabrication conditions were as followed: the ratio between monomer and porogen was 4/6;the percentages of BMA,EDMA and AMPS in the monomer were 59.5%,40%,0.5%,respectively;the percentages of 1,4-butanediol,1-propanol and water in progen were 62%,28% and 10%,respectively.The of poly(BMA-EDMA-AMPS)monolithic column with typical reversed-phase separation mechanism was uesd to achieve peptide separation in pressurized capillary electrochromatography.In the third chapter,?-methacryloxypropyltrimethoxysilane was used to modify fumed silica nanoparticle(FSNP)to synthesize methacryloyl fumed silica nanoparticle(MFSNP).Hybrid poly(GMA-EDMA-MFSNP)monolithic column was fabricated by in-situ copolymerization of MFSNP with glycidyl methacrylate(GMA),ethylene glycol dimethacrylate(EDMA)as monomers and dodecyl alcohol,cyclohexanol as binary porogens.With ring-opening reaction of GMA,phenylalanine was modified on the surface of the monolithic column.In order to obtain high efficiency,permeability and electroosmotic flow(EOF),the contents of the polymerization mixture and the chemical modification conditions of phenylalanine were optimized.Satisfactory separations of various analytes such as alkybenzenes,polycyclic aromatic hydrocarbons,benzoic acid analytes,phenol analytes and peptides have been achieved on the zwitterionic monolithic column prepared under the optimal conditions by pressurized capillary electrochromatography.In the fourth chapter,epinephrine was bonded on the hybrid poly(GMA-EDMA-MFSNP)monolithic column prepared under optimal conditions dercribed in charpter three to obtain E-poly(GMA-EDMAMFSNP)monolithic column.The modification condition of the epinephrine was optimized.The monolithic column was used to separate the five alkaloids in pressurized capillary electrochromatography.Applied to real sample,good resolution of 3 alkaloids Chinese medicine compounds Huanglian Shangqing capsule were also achieved.The fifth chapter summarized this research and looked into the possible research directions in the future.