Amphiphilic Silica Gel Stationary Phases: Preparation And Their Applications In Separation And Analysis Of Phospholipids

Phospholipids are one of the most important biological lipids.They are the main components of biological membranes and play important structural,metabolic and functional roles.In addition,phospholipids are involved in cell death and cell signaling,and are associated with the occurrence and development of various neurodegenerative diseases and tumors.Due to their biochemical and clinical importance,rapid and reliable analytical methods are needed to identify and quantify phospholipid molecules in complex biological samples.In this paper,according to the structural characteristics of phospholipids,modified styrene-maleic anhydride copolymer(SMA)and dodecyl phosphodiester(P-C12)were introduced into the preparation of chromatographic stationary phase.Thus,the modified styrene-maleic anhydride copolymer stationary phase(Sil-SMA-MME)and alkyl phosphate modified stationary phase(Sil-P-C12)were fabricated.Their potential applications in phospholipid separation and analysis was also researched.The first chapter mainly contains four parts.The first part introduces the structure and composition of phospholipids,the physiological function of phospholipids and their separation and analysis method.In the second part,the application,synthesis and solubilization function of SMA for membrane lipids were introduced.The third part introduces the properties of phosphate ester and their application in the chromatographic stationary phases.The fourth part describes the research ideas and innovations of this paper.In the second chapter,with styrene and maleic anhydride as the monomers,the Sil-SMA-MME stationary phase was prepared by grafting SMA onto the silica gel surface through click reaction and free radical polymerization reaction,followed by ring opening reaction with methyl methionine hydrochloride(MME·HCl).The fabricated Sil-SMA-MME stationary phase was characterized by thermogravimetric analysis and Fourier transform infrared spectroscopy,respectively.The Sil-SMA-MME column is of typical hydrophilic interaction retention mechanism,and the column efficiency can reach 90,900 N/m.The Sil-SMA-MME column can realize the efficient separation and analysis of sulfonamides,amides,flavonoids,nucleosides and nucleic acid bases and phenols.In the third chapter,dodecyl phosphodiester was synthesized with phosphorus oxychloride and dodecanol as the monomers,and then bonded on the surface of amino modified silica gel so as to prepare the Sil-P-C12 chromatographic stationary phase.The Sil-P-C12 stationary phase material was characterized by thermogravimetric analysis and Fourier transform infrared spectroscopy,respectively.The Sil-P-C12 column is of reversed-phase/hydrophilic mixed-mode retention mechanism.The excellent separation performances of the Sil-P-C12 column was verified by thiocarbamides,sulfanilamides,phenols,amides,flavonoids,nucleosides and nucleic acid bases and alkylbenzenes.In the fourth chapter,the Sil-SMA-MME column and Sil-P-C12 column were used for the separation and analysis of phospholipid standards,phospholipid extracts from Antarctic kril oil,soybean lecithin,human serum as well as breast cancer cell membrane.The two columns could realize the effective separation and analysis of different phospholipid classes and species.Both of the two columns show a certain potential in separation of complex phospholipid samples.The fifth chapter is the summary and prospect of this work.