Construction Of Protein/Phospholipid/Cholesterol Hybrid Microvesicles And Study Of Its Performances

With the development of technology and social progress,humans are more curious about the origin of cells,and artificial cell models are the product of this interest.At present,the method of designing and constructing microscale vesicle models through bottom-up synthesis has attracted wide attention in the scientific community.The main microscale vesicle models include liposomes,polymersomes,proteinosomes,etc.The limitations of single-component vesicles have prevented the rapid development of vesicle models.In order to make up for the deficiency of the function of single component vesicles,the subject constructed multiple hybrid microscale vesicles based on hydrophobic interaction with the main components of the natural cell membrane?protein,phospholipid,cholesterol?,integrating the advantages of various components and endows them with functions and properties similar to those of real cells.Using BSA?bovine serum albumin?,cholesterol and N-isopropylacrylamide as raw materials,BSA-NH₂,cholesterol monomer,carboxylated cholesterol,poly?Nisopropylacrylamide?and cholesterol monomer block copolymer,etc.,were synthesized through esterification and reversible addition-fragmentation chain transfer polymerization?RAFT?,then coupled to prepare two amphiphilic couplers,and amphiphilic coupler were characterized and quantitatively analyzed;Finally,using these two amphiphilic couplers as primitives,the protein vesicles were prepared by Pickering microemulsion method,and then assembled with phospholipids for a second time,thus smoothly constructing hybrid microvesicles with uniform size and stable properties,which had better biocompatibility,membrane fluidity,heat stability,thermal sensitivity and other Functions and advantages.Taking one of the multiple hybrid microscale vesicles as the research object,the morphological characteristics of the vesicles were observed by SEM.Based on the fluorescent bleaching recovery technique and the one-dimensional diffusion equation,the fluidity of the membrane was discussed.The comparison found that the membrane flow size of the constructed hybrid microvesicles is the same order as that of the red blood cell membrane(Constant is 1×10^-9 cm²/s),and its diffusion constant is 4.8×10^-9 cm²/s.The structural characteristics of vesicle membranes are similar to those of natural cell membranes.Finally,FITC-Dextran with different molecular weights was used to analyze the permeability of microvesicle membranes.The results showed that the membrane permeability was 30 KDa,thus achieving the functional characteristics of vesicle membranes to control the entry and exit of substances.