Study On Properties And Application Of Lysozyme Grafted Polyzwitterion Antifouling Coatings

Biofouling is undesirable in many medical,marine and industrial sectors.Developing a simple field and general strategy for surface modification of a wide variety of materials has proven to be extremely challenging.In order to solve the above problems,this work developed a broad-spectrum antifouling coating preparation method based on poly-2-methacryloyloxyethylphosphorylcholineconjugated lysozyme(lyso-PMPC)amyloid-like aggregates.The intramolecular disulfide bonds of lyso-PMPC were broken by the reducing agent tris(2-carboxyethyl)phosphine hydrochloride(TCEP),and a phase transition occurred to rapidly form an emulsion of amyloid aggregates.By simply dipping or spraying,a dense,colorless and transparent 2D nanofilm(thickness about 10 nm)can be grown on any substrate—we named PMPC-PTL nanofilm.Our work highlights the universality of PMPC-PTL nanofilms for surface modification of materials,which is not inferior to the current popular polydopamine system,and provides a new research direction for the material community.Our main work is as follows:(1)Coupling of polymer PMPC with lysozyme and its film formationWe grew polyzwitterions in situ on the surface of lysozyme by classical atom transfer radical polymerization(ATRP).The successful coupling of lysozyme to PMPC was confirmed by mass spectrometry,XPS and infrared spectroscopy.We prepared PMPC-PTL nanofilms by two simple methods: spraying or immersion,and characterized the morphology of the films under different reaction conditions by atomic force microscopy(AFM).By growing PMPC-PTL nanofilms on different substrates,it shows that it is a universal material surface modification material.(2)Antifouling coating based on PMPC-PTLDue to the presence of polyzwitterionic polymer brushes and amyloid-like structures,PMPC-PTL membranes have excellent antifouling capabilities against various biological contaminants including biomolecules,biological fluids,and cells.The coating inhibits the adhesion rate of gram-negative bacteria and gram-positive bacteria by more than 95%.We also conducted experiments on its anti-fungal adhesion ability.Through optical microscopy,we found that the surface of the material grown with PMPC-PTL nanofilm can resist the adhesion of Candida albicans,Aspergillus flavus,Aspergillus niger and Penicillium citrinum.This shows that it is expected to show its talents in fruit preservation.At the same time,PMPC-PTL nanofilms can inhibit the adhesion of fibroblasts and platelets,showing their potential as wound dressings.PMPC-PTL nanofilms have superior hemocompatibility and cytocompatibility.It can be seen from the hemolysis experiment that the hemolysis rate of PMPC-PTL nanofilm is 1.3%,which is lower than the international standard of 5%.The results of MTT experiments showed that PMPC-PTL nanofilms had no cytotoxicity.Platelet adhesion is another common problem associated with blood clots when the device is in contact with blood.Due to the excellent antifouling ability of PMPC-PTL nanofilm,it can be used in blood contact devices.This versatile,easily scalable,biofouling-resistant surface treatment can improve the safety of implantable devices.