Synthesis And Characterization Of Phosphorylated Silver Nanoparticles Modified Polyurethane Antibacterial Material

PU is short for polyurethane,which is the general term for polymer containing repeat urethane groups in the polymer main chain structure.Polyurethane material can replace rubber,plastic,nylon,etc.,and are widely used in many areas such as health care,home appliances manufacturing,home decoration,agricultural production,textile manufacturing,and transportation.Polyurethane material has strong chemical resistance,good biocompatibility and its toxicity results meet the medical requirements.The material will not cause distortion and allergy.Furthermore,polyurethane material can be treated with usual sterilization methods without affecting its performance,and has excellent toughness and flexibility,easy to process,so it has become the first choice of producing medical elastomer products.Thus polyurethane material plays a very important role in biomedical polymer materials,and is widely used in artificial heart,artificial kidney,artificial skin,bandages,accessories,drug delivery,all aspects of catheter interventional treatment,family planning supplies,etc.With the development of modern medicine,the application of medical polyurethane material is increasingly widespread.However,a lot of problems are also found during the applying course,particularly the aftermath caused by bacterial infections,which is too serious to ignore.For the biological function materials being easily infected by bacterial,which affects human health and even threatens life,bring significant economic losses,in the present situation of clinical application and development trend of polyurethane materials,research and preparation of biomedical functional materials with antibacterial properties using polyurethane substrate is particularly important.Most antimicrobial material adds antibacterial agent in the substrate to achieve the antibacterial effect.Conventional antimicrobial agents include inorganic,organic,and natural antibacterial agent.Inorganic antibacterial agents are generally metallic materials,such as silver,copper,zinc and silver and other current rapidly developing containing silver antimicrobial material,copper stainless steel,titanium,etc.Organic antimicrobial agents are organic compounds with antibacterial properties,such as ethanol,lauryl arsenic,p-nitrophenol,ethylene-methyl ether and the like,but mainly in small organic molecules.The organic antibacterial agent has advantages in high sterilization speed,high anti-bacterial efficacy,easy processing,and shortcomings in poor heat resistance,easy precipitation in aqueous environments,causing drug resistance when used alone.Natural antibacterial agent is mostly extract of natural animals and plants,commonly used natural antibacterial agents are chitosan,Protamine,cinnamon oil,cypress oil and allicin and so on.Natural antimicrobial agent has advantages in high antibacterial efficiency,safety and being nontoxic.But the difficulties in processing,extracting,poor heat resistance,limit its application.The inorganic antibacterial agent Ag+ is one of the metal ions with the lowest minimum inhibitory concentration,and is non-toxic and colorless.So Ag+ is very useful as an antibacterial agent when added to the substrate.Nanosilver is a new developed nanotechnology-based antimicrobial materials with large surface area.When in water or aqueous solutions,nanosilver act as:Ag=Ag++e-.Because of its quantum effect,small size effect,great surface area,and unmatched superior antimicrobial efficacy and safety to traditional inorganic antibacterial agent,nanosilver is an antibacterial agent with long-term resistance and weather resistance.However,nanosilver has cell cytotoxicity and exists the problem of poor biocompatibility.This subject planned to prepare an antibacterial materials by adding antimicrobial agents to polyurethane.First select inorganic silver nanoparticles with excellent antibacterial properties as the antibacterial agent,improve its biocompatibility by phosphorylation.Then modify the surface of polyurethane materials with phosphorylated silver nanoparticles by sedimentation method to get nanocomposite material own both excellent antibacterial properties like silver nanoparticles and good biocompatibility.Furthermore,coat polyurethane on the homemade acellular stent surface,then prepare vascular patch by modifying phosphorylation silver nanoparticles to the surface of polyurethane/acellular stent.Research the physical properties,antibacterial properties and biocompatibility of materials by SEM,TEM,NMR-P,EDS,SCA,TG,XPS,tensile properties test,bacterial adhesion experiments,film antibacterial test,antimicrobial performance test,in vitro cytotoxicity assays,blood compatibility test and animal experiment.Finally we get one new composite material,which gains better biocompatibility than polyurethane while maintaining the antibacterial ability of inorganic nanosilver,and the result of in vivo animal experiments is good.Thus the subject provide a new material for future treatment of vascular diseases.