Preparation And Applications Of Multifunctional Ultrafine CA Mats

Electrospinning is a simple and convenient method to prepare micro/nano structural fibers with high specific surface area,high porosity and certain mechanical strength.Cellulose acetate(CA)is a biocompatible and hydrophilic cellulose ester which is cheap and has good performance.This thesis is mainly based on the electropinning technology to prepare a series of multifunctional cellulose acetate ultra-fine membranes.(1)The boric acid-functionalized electrospinning acetate cellulose membrane was synthesized through visible light-induced grafting polymerization to enrich and separate glycoproteins.First,ultra-fine cellulose acetate membrane was successfully prepared with uniform diameter by electrospinning.Then boric acid groups with different grafting density were introduced on the electrospinning membranes through visible light-induced grafting polymerization method.Finally,the enrichment,separation and recycle performance of the boric acid-functionalized electrospinning membrane was tested by adsorbing and stripping experiments in a single Ovalbumin protein and a complex egg white protein.Experimental results showed that the boric acid functionalized-electrospinning acetate cellulose membrane can selectively adsorb and separate mass glycoproteins.In addition,the high stability and selectivity of the membranes were retained after several separation cycles.(2)A kind of multifunctional electrospinning acetate cellulose membrane platform applied to post-modification was built using sulfonyl fluoride exchange(SuFEx)reaction.First,we succeeded in synthesizing polymer PSO2F with sulfonyl fluoride group.Then acetate cellulose membrane platforms with different sulfonyl fluoride content were prepared by adjusting feed ratios of PSO2F and cellulose acetate in the process of electrospinning.Based on the "click" chemistry of sulfonyl fluoride and silicon ether groups,we successfully introduced different functional groups and polymer such as red dye disperse red 1,alkynyl,alkenyl sulfydryl and PEG on the surface of membrane.(3)Combined with Schiff base reaction,we described a simple,substrate-independent protocol to prepare a lysine-ligand functionalized layer on biomaterial surfaces.This approach is based upon the cross-linking and adsorption of aldehyde-functionalized poly(N-(2,2-dimethoxyethyl)methacrylamide)(APDMEA)and amino-functionalized polymethacryloyl-l-lysine(APMLys)on all kinds of substrates,such as polyurethane(PU)and polyvinylchloride(PVC).The fibrinolytic activity was realized by the specific affinity between ?-lysine ligand and plasminogen.This method can not only be adapted to various materials,including all kinds of polymer surface,PDMS and metal surface,but also be easily adjusted lysine content on the surface to improve the fibrinolytic activity.Experimental results showed that the lysine-ligand functionalized layer on substrates highly enhanced the specific adsorption of plasminogen from plasma and had good chemical stability and excellent biocompatibility.