PHEAA-b-PFMA Brush Modified Surfaces:the Microphase Separation Behavior And Resistance To Protein Adsorption

Nonspecific protein adsorption brings severe challenge to biomaterials,such as implant materials,medical device,and biosensors.The adsorbent nonspecific protein on biomaterials surface usually leads decreased performance of medical device and increased rejection reaction or bacterial infection of implant materials.In recent two decades years,surface modification as an effective method is extensively developed and applied in regulating and resisting the interaction between proteins and surfaces.There are a number of strategies for surface modification.Among them,polymer brush as a surface modification method attract much attention due to its diversity,easy modification,and good biocompatibility.According to the difference of surface property,surfaces modified by polymer brush can be divided into the hydrophilic,hydrophobic,and low surface energy.From the point of the structure and component,the modified surfaces can also be divided into homogeneous and heterogeneous.Compared to the homogeneous polymer brush modified surfaces,the latter generously possesses the more high efficiency and long term anti-protein adsorption performance.In this paper,we fabricated a serial of amphiphilic block copolymers brush(PHEAA-b-PFMA)modified silicon surfaces via successive surface-initiated atom transfer radical polymerization(SI-ATRP).And then we investigated the microphase separation behavior and anti-protein adsorption performance of the block copolymer brush modified silicon wafers.In chapter 1,we mainly introduced and summarized the strategies,as well as the common polymers for resisting proteins adsorption.According to the surface structure and chemical composition,we overviewed the methods and materials used in surface modification.In chapter 2,we synthesized a series of PHAA and PHEAA-b-PFMA brush modified silicon wafers via SI-ATRP and then studied the effect of parameters on the microphase separation behavior of PHEAA-b-PFMA.Only when the grafting density(?),thickness of PHEAA brush,and the ratio of PFMA/PHEAA were in the range of 0.9-1.3(chain/nm2),6.6-15.lnm and 89/42-89/94,could PHEAA-b-PFMA phase separate into worm-like structure.Finally,we chose BSA,Fibrinogen,Lysozyme and IgG as the model proteins to investigate the anti-adsorption performance of PHEAA and PHEAA-b-PFMA modified surfaces.The results indicated that most of the modified surfaces could obviously reduced the protein adsorption compared to the pristine silicon wafers.And with the increase of molecular weight,the antifouling performance increased.For Fibrinogen,the anti-adsorption effect of PHEAA-b-PFMA modified surfaces with both separated sizes were better than corresponding PHEAA.However,there was no obviously enhanced anti-adsorption performance after the introduction of fluorine containing units in PHEAA-b-PFMA for other proteins.