Study On The Non-destructive Transmembrane And Antibacterial Properties Of Water-soluble Conductive Polymers

Microbial contamination and drug-resistant bacteria infection have become one of the biggest threats to public safety,and the main challenge facing the antimicrobial field is to overcome the low permeability of bacterial membranes that protect cells from various drugs.In this paper,the enzyme-mimetic aqueous synthesis method,which is of great significance to the phase capacity of the biological system,was used with Poly（sodium-p-styrenesulfonate）（PSS）as a template,Fe POs as catalyst and H₂O₂as initiator.Water-soluble conductive polymers,PANI:PSS[Polyaniline:poly（p-styrenesulfonic acid）],PEDOT:PSS[Poly-thiophene:poly（p-styrenesulfonic acid）]and PPy:PSS[polypyrrole:poly（p-styrenesulfonic-esulfonic acid）]were synthesized,which can penetrate the cell wall,cell membrane and other structures of bacteria directly with its non-disturbing translocation.Since they have fluorescence characteristics,the Confocal laser scanning microscope（CLSM）was used to determine the localization of them,confirming that they can quickly enter into bacteria after incubating with bacteria for 5 min.At the same time,the photothermal antibacterial effect of PANI:PSS and PEDOT:PSS after being rapidly taken up by bacteria were studied by SEM,TEM,Life/death staining,CLSM,etc.under the near-infrared irradiation of the 808 nm laser,the PANI:PSS and PEDOT:PSS inside the bacteria relied on its excellent photothermal effect to produce local hyperthermia inside the cell and effectively killed the bacteria,as well as their biofilm structures,such as Staphylococcus aureus（S.aureus）,Methicillin-resistant Staphylococcus aureus（MRSA）and Escherichia coli（E.coli）.Finally,the results of in vivo antibacterial experiments,blood routines,and tissue staining sections have proved the good biocompatibility of water-soluble PANI:PSS with excellent antibacterial activity,as well as PEDOT:PSS,showing great potential in the treatment of various bacterial infections.The specific research content and results are as follows:1.Preparation of water-soluble conductive polymers PANI:PSS,PEDPT:PSS and PPy:PSS:1)Synthesis of Fe POs,Cu POs Nanozyme:dd H₂O was used as the solvent,phosphoric acid,urea and ferrous chloride tetra hydrate（Fe Cl₂·4H₂O）,Copper sulfate pentahydrate（Cu SO₄·5H₂O）were used as raw materials for the reaction.Under the catalyzed conditions of ethylene glycol and Polyvinyl-pyrrolidone（PVP）,it is prepared under high temperature and high pressure for 24 h.2)Preparation of water-soluble polymers:Fe POs and Cu POs nanoenzymes with the properties of peroxidase mimics were used as catalysts,with aniline and3,4-ethoxylene dioxy thiophene（EDOT）,Pyrrole were as the monomer,sodium polystyrene sulfonate was the template,and hydrogen peroxide was the initiator.A series of water-soluble conductive polymers have been successfully synthesized by the enzyme-simulated water synthesis method.The reaction conditions were mild,the product was non-toxic,environmentally friendly,and the product has good water solubility,excellent photothermal performance and non-destructive transmembrane performance.This provides an important idea for the development of new antibacterial agents and the improvement of antibacterial efficiency.2.Evaluation of water-soluble conductive polymers PANI:PSS and PEDOT:PSS of their antibacterial effect:PANI:PSS and PEDOT:PSS solutions of different concentrations were irradiated by near-infrared lasers at different power densities,which proved that the polymers prepared by the enzyme-simulated aqueous synthesis method have an excellent photothermal heating effect and good photothermal cycle stability.The photothermal conversion efficiency of PANI:PSS and PEDOT:PSS were as high as 40.6%,46.4%（2.0 mg/m L,808 nm,1.0 W/cm²,5 min）,respectively.S.aureus,E.coli,and MRSA were used as bacterial models to study the photothermal antibacterial effect of water-soluble PANI:PSS and PEDOT:PSS.The results showed that under near-infrared laser irradiation（808 nm,1 W/cm²,5 min）,the photothermal antibacterial effect of PANI:PSS was significant,and the survival rate of S.aureus,E.coli and MRSA were 1.41±1.1%,0.97±0.11%and 4.14±2.01%,and the PEDOT:PSS had better treatment outcomes.The mouse embryonic fibroblasts（3T3）and mouse fibroblasts（L929）were used as normal cell models to study the toxic and side effects of PANI:PSS,PEDOT:PSS at different concentrations on normal somatic cells.The results showed that,the cell viability was still as high as 95%.In addition,in the hemolysis test,when the dose of PANI:PSS and PEDOT:PSS reached0.5 mg/m L,the hemolysis rate was only 2.7%,without significant hemolysis,which further verified the excellent photothermal effect and biological safety of water-soluble PANI:PSS,PEDOT:PSS.The 6-8 week old ICR white mice weighing 16-20 g were used as animal models to create S.aureus and MRSA wound infection models,and to study the in vivo photothermal antibacterial effect of water-soluble PANI:PSS.The results showed that on the eighth day after the photothermal treatment,the wounds in the PANI:PSS+NIR group were almost completely healed,while the wounds healing in the Control group,NIR-only group and PANI:PSS-only group were similar and far worse.After the treatment,the mice were euthanized and their wound skin tissues and main organs were taken for pathological analysis,which further proved the excellent photothermal antibacterial effect and biological safety of water-soluble PANI:PSS.3.Evaluation of non-destructive membrane penetration of water-soluble conducting polymers by enzyme-simulated aqueous synthesis method:To further highlight the superiority of the enzyme-simulated aqueous synthesis method for preparing water-soluble polymers,PANI:PSS,PEDOT:PSS and PPy:PSS were synthesized,the water-solubility and spontaneous non-destructive translocation membrane penetration properties were studied by fluorescence colocalization,which further demonstrating the great potential of enzyme-mimetic aqueous synthesis to prepare water-soluble polymers in the field of antibacterial.It provides important ideas for the development of new antibacterial agents and the improvement of antibacterial efficiency.