The Preparation And Characterization Of Grapheme Based Antibacterial Compounds Modified By Water Soluble Polymer

At present, the extensive use of disinfectant pollute the environment, and causegreat damage to human body health. Although inorganic antibacterial materialscarried with silver shows good security and long-term effect,Its shortcomings of highprice、weak antibacterial activity、worse discoloration property limit its extensiveapplication.So, it will become a research hotspot in the field of antibacterial materialto develop high level of security and stability water-soluble long-acting antibacterialmaterials.Graphene sheets-one-atom-thick two-dimensional layers of covalent bondedcarbon are novel carrers for a variety of functional materials with series of excellentphysical, chemical and biological properties.Therefore, based on the research ofantibacterial properties of grapheme（rGO） and graphene oxide（GO）, We use watersoluble polymer poly lysine （PLL） and triblock amphiphilic copolymerpolyoxyethylene-poly（propylene oxide）-polyoxyethylene （Pluronic F127） to modifythem. And then loaded them with nano-copper or zinc ions, obtain a series of watersoluble graphene based antibacterial compounds, and studies their structure andproperties.First of all, the antibacterial activity of graphene and graphite oxide have beenstudied, and the changing of the ion concentration of bacterial cell have beenmeasured. Experiments showed that the graphene oxide has excellent antibacterialactivity when concentration is above3000ppm, the antibacterial rate can reached100%when contact with E. coli and S. aureus6h. The antibacterial effect of grapheneoxide is changing ion channels of bacterial and make its ion dissolution, resulting inbacterial death due to loss of physiological activity.Second, modified graphene oxide with poly lysine （PLL） to obtain water solubleGO-PLL.Then loaded copper, poly lysine-graphene-nanometer copper complexesPLL-rGO-CuNPs is obtained by reducted with hydrazine hydrate. The microstructureand properties are analyzed. When the concentration is100mg/L,it founded to remainstable without visible precipitate for more than3months, showing excellent watersolubility. The antibacterial rate reached99.99%and99.58%respectively when contact with E. coli and S. aureus24h while the concentration is16.3mg/L.PLL-rGO-CuNPs exhibited better delayed-releasing effect than PVP–CuNPs. Theantibacterial effect of PLL-rGO-CuNPs is also obtained by changing ion channels ofbacterial.Finally, respectively modified the oxidized graphene （GO） and graphene （rGO）with Pluronic F127, and then loaded with zinc ions. Pluronic F127-graphene-zinc ionscomplexes Pluronic F127-rGO-Zn²⁺and Pluronic F127-graphene oxide-zinc ionscomplexes Pluronic F127-GO-Zn²⁺are obtained. Study the water solubility andantibacterial property.Results show that Pluronic F127-rGO-Zn²⁺and PluronicF127-GO-Zn²⁺had very good solubility in water, and founded to remain stablewithout visible precipitate for more than3months. And their antimicrobial activityperformance had greatly improved compared to the pure zinc ions. The antibacterialrate of Pluronic F127-rGO-Zn²⁺and Pluronic F127-GO-Zn²⁺all reached99%whencontact with E. coli and S. aureus24h while the concentration is50mg/L,showedgood antibacterial activity.