The Research On Controllable Preparation Of Photothermal Nano-metal-polymers And Bacterial Inhibition Property

At present,bacterial resistance problem caused by the abuse of antibiotics is becoming austere.At the same time,the antibiotics overuse has adverse impact to the environment and would destroy the ecosystem.Photothermal and photodynamic physical materials have attracted more attention in antibacterial field based on their non-invasiveness and efficient antibacterial properties.The development of new eco-friendly and efficient antibacterial materials and green synthesis methods is of great significance in bacterial inhibition and environmental protection.The assembly of metal ions with natural molecular is an effective way for fabrication of functional and eco-friendly photothermal nanomaterials.Meanwhile,it is of significance for the development of new eco-friendly material synthetic methods and research on controllable assembly and biosynthesis methods to reduce the pollution caused by the material preparation process.In this paper,five different photothermal nano-metal polymer materials were fabricated and their low-energy preparation methods were studied.The antibacterial mechanisms of the photo-activated materials were explored to achieve effective bacteria inhibition.The main research results of this paper are as follows:(1)Novel protein microfibers(MS@BDA@Au)with bacterial filtration abilities were developed with metal-protein assembly induced by biological cations and anions.Three types of MS@BDA microfibers were fabricated through the assembly of proteins-dopamine(DA)with M²⁺(Fe²⁺,Cu²⁺,Mn²⁺)/Na₂S.Further,the decoration of gold to microfibers produced MS@BDA@Au microfibers.It was found that MS@BDA@Au had excellent ability for bacterial filtration,which exhibited a filtering capacity of 1×10⁸CFU bacteria per milligram.Meanwhile,the microfiber showed obvious antibacterial effects at concentrations of 0.5 mg·mL^-1 with treatment of NIR laser with 99.8%bacterial inhibition rate.(2)The self-assembly conditions of bovine serum albumin(BSA)with the NH₂-NH-CO-groups conjugated porphyrin(P)and polyphenols(caffeic acid,CA)were researched to constructed a photo-responsive microfiber(PCA@BSA).The decoration of gold provided the microfiber(PCA@BSA-Au)with photothermal ability and intensive affinity with bacteria.It was found that CA encapsulated in PCA@BSA-Au could be released when protons were produced.Moreover,the bacteria made fibrosis be slimer and longer microfibers.Biological evaluation unveiled excellent photo-driven(808 nm and red LED)antibacterial capability.It shows that PCA@BSA-Au is a kind of polyphenols transporter with bacteria selective enrichment and photothermal effect.(3)The surface modification and assembly method of nanoparticles by E.coli and the iron(?)and Na₂S₂O₃ in the culture solution was studied to synthesize two new metalloprotein porphyrin nanoparticles with good photothermal properties:P@BE and PCA@BE/P+CA@BE with same components but different morphology.It was found that the nanomorphology of nanoparticle changed through E.coli sculpturing metalloprotein porphyrin,and the sculpturing process was affected by the small molecules wrapped by the protein.The recognition of P+CA@BE for bacteria was further explored by electrochemical analysis.Results demonstrate that P+CA@BE could distinguish E.coli and S.aureus(Staphylococcus aureus).Meanwhile,P+CA@BE showed different inhibitory effects on E.coli and S.aureus,which had a better inhibitory effect on S.aureus.The results show that surface biomineralization of materials by microorganism could be developed for the preparation of bacterial selective biomaterials.(4)The modification methods of cellulose terephthalate and interfacial synthesis of sulfide bridged metal porphyrin were researched and a polyporous metal porphyrin modified cellulose terephthalate(CMF@PCNCu)was fabricated.CMF@PCNCu exhibited excellent antibacterial capacity by interfering with pyruvic acid metabolism at a low-dose of 25?g·mL^-1 and even at a smaller dose of 10?g·mL^-1 with synergistic photothermal cure.Moreover,CMF@PCNCu could absorb 6.8×10⁷ CFU of bacteria per milligram,with well bacterial absorption efficiency after three cycles.The results validate CMF@PCNCu is a kind of functional cellulose to interfere bacterial metabolism.(5)The one-pot polymerization method of europium(?)doped poly(p-amino benzoic acid)polymer fused Fe³⁺coordination polymer was studied and an artificial mimic photosystem II nanoparticle(PPaba-FeEu@GO)were constructed.The PPaba-FeEu@GO showed enhanced electron mobility,hole diffusion distance and TOF value of 125 h^-1,meanwhile with well stability in morphology and chemical property.PPaba-FeEu@GO had a good light-driven performance to release active oxygen and well photothermal ability which could inhibit almost 100%bacteria.