Study On The Screening Of Antimicrobial Peptides And Separation Of Chiral Drugs Based On Chromatographic Fillers Based On Modified Functional Microsphere

Modified functional microspheres are a kind of microspheres with more powerful functions modified on the surface of the original microspheres.Modified functional microspheres are widely used in the field of drug separation.It is well known that the screening and purification of drugs are of great significance to human health.The low purity of drugs will lead to poor efficacy and even adverse reactions.Among them,the two drugs represented by antimicrobial peptides(AMPs)and chiral drugs are faced with the problems of difficult drug screening and insufficient purity.AMPs have broad-spectrum antibacterial activity and diverse mechanisms of action.AMPs have good biocompatibility and can overcome the current crisis of bacterial resistance.However,due to the wide variety of antimicrobial peptides,screening is time-consuming and laborious.In addition,chiral drugs are very common in daily life.Their physical and chemical properties are basically similar except for optical activity,there are great differences in biological activity,metabolic process,pharmacology and toxicology.Based on the above problems,this project has successfully developed a membrane chromatographic filler for screening target peptides.The membrane chromatographic filler uses silica microspheres as the carrier,and the bacterial membrane is coated on the surface of the microspheres.The peptide chain with antibacterial effect is screened from the peptide library by high performance liquid chromatography,and a series of characterization tests are performed on the peptide chain.In addition,we also prepared a chromatographic packing that can separate chiral drugs and tested its separation effect.The main work and conclusions are as follows:Silica microspheres were prepared by modified St(?)ber method,and water-soluble photosensitive polymer diazoresin(DR)was synthesized.The bacterial membrane were modified to the surface of silica microspheres by DR to realize the functional modification of silica microspheres,and the membrane chromatographic packing of Escherichia coli and Staphylococcus aureus was obtained.The short peptide FWKFK with antibacterial properties was successfully screened by using the membrane chromatographic packing.The method is non-toxic and environmentally friendly,the operation is simple and the product is stable,which has certain potential value and guiding significance for the development of membrane chromatography in the future.In addition,the stability,antibacterial properties and biocompatibility of FWKFK were tested.The antibacterial properties and biocompatibility of antimicrobial peptides were verified at the cellular and in vivo levels.In the mouse wound bacterial infection model,it showed excellent antibacterial and wound healing effects.In addition,this thesis adopts the improved preparation method of polystyrene seeds.By optimizing the reaction conditions,such as adding polymerization inhibitors and adjusting the content of azodiisobutyronitrile(AIBN),polystyrene seed microspheres with uniform and controllable particle size and good monodispersity were successfully prepared.It solves the problem that the traditional polystyrene microsphere seeds limit the application of preparing large-sized polymer microspheres due to the large molecular weight.In addition,PMMA microspheres were prepared by polystyrene seeds and carboxylated by hydrolysis.β-cyclodextrin was modified by 4-chlorophenyl isocyanate.PMMA microspheres and modified cyclodextrin were coupled by DR to prepare a new type of chromatographic filler.Four different chiral drugs were separated by high performance liquid chromatography.