Antibacterial Properties Of Cationic-zwitterionic Copolymers And PCL Blending Films

Bacterial infection of medical instruments endangers patient's life and health,this paper combined with the advantages of cationic and zwitterionic,blend with poly(?-caprolactone)(PCL)to prepared antibacterial blend films,and explored the relationshio betweent blend surface element composition and content,surface morphology and antibacterial activity,biological compatibility.Reversible addition fragmentation chain transfer polymerization(RAFT)was used to synthesize PDMA and PDMA-b-PSBMA copolymer,and prepared the products of quaternary ammonium salts(QPDMA).QPDMA quaternalization degree were 21%,45%and 71%respectively,and Zeta potential increased with the increase of ammonium degree.The ratio of PDMA:PSBMA in the block copolymers were 140:28,140:45 and 140:57,and their PDI were between 1.02-1.10,indicating a narrow molecular weight distribution.Antibacterial test results shown that PDMA had the best antibacterial effect,the minimal inhibition concentration on E.coli and S.aureus were 256?g/mL and 128?g/mL.The results of anti-adhesion test showed that the introduction of zwitterionic could effectively reduce the adhesion of BSA.Blend films of different proportions were prepared by the solution blending method with PCL and PDMA-b-PSBMA.XPS results showed that the N,S elements on the surface increased with increasing content of copolymer composition;When the PDMA-b-PSBMA content was 30%,AFM results showed a minimum roughness of R_q 12.8nm.The anti-adhesion tests of bacteria,BSA and platelets were proved to have excellent antifouling properties.The blend films developed clearly inhibition circle for S.aureus and E.coli,the Live/Dead staining image illustrated the synergistic effect of bactericidal and anti-adhesion.When the PDMA-b-PSBMA content was 30%,relative cell viability was about 80%and all of the hemolysis was below 2%,showed good biocompatibility and antibacterial activity,the blend film may be a promising antimicrobial material.Blend films were cultured with medium for 8days,after which,the surface roughness increased and appeared fold and holes,the wettability decreased a little,while still had a certain resistance to bacterial adhesion and sterilization effect.The PCL/PDMA-b-PSBMA blend films have a good application prospect in catheter,litters and other biomedical materials.