Ag/Fe_3O_4/rGO纳米复合材料的制备及抗菌性能

以四水合氯化亚铁和硝酸银为原料,硼氢化钠为还原剂,氧化石墨烯(GO)为载体,通过原位还原法制备了具有磁分离功能的银/四氧化三铁/还原氧化石墨烯(Ag/Fe_3O_4/rGO)纳米复合抗菌材料.采用X射线粉末衍射仪(XRD)、X射线光电子能谱仪(XPS)、透射电子显微镜(TEM)等对复合材料进行了表征.结果显示,Fe_3O_4和Ag纳米颗粒均匀分布在rGO片层上.复合材料的饱和磁化率(Ms)为40.5 A·m~2·kg·(-1),表明其具有较强的磁性,将其与菌液混合后,在磁场作用下10 min即可吸附沉降完成磁分离.以大肠杆菌(E.coli)和金黄色葡萄球菌(S.aureus)为实验菌株,通过琼脂扩散法评价了复合材料的抗菌性能.结果表明,该复合材料具有良好的抗菌效果,对E.coli和S.aureus的抑菌圈直径分别为18 mm和13 mm,最低抑菌浓度值(MIC)分别为50 mg/L和80 mg/L,最低杀菌浓度值(MBC)分别为30 mg/L和50 mg/L.

Preparation and Antibacterial Properties of Ag/Fe3O4/rGO Nanocomposite

Antibacterial sliver/ferroferric oxide/reduced graphene oxide (Ag/Fe3O4/rGO) nanocomposite with magnetic separation performance was prepared by in situ reduction method with FeCl2 · 4H2O and AgNO3,using NaBH4 as reducing agent and graphene oxide (GO) as the carrier.The nanocomposite was characterized by X-ray powder diffraction(XRPD),X-ray photoelectron spectroscopy(XPS) and transmission electron microscopy (TEM).The results showed that the Fe3O4 and Ag nanoparticles were uniformly distributed on the rGO sheets.Hysteresis loop test results indicated excellent magnetism of the nanocomposite,the saturation susceptibility(Ms) was 40.5 A · m2 · kg-1.Adsorption and settling of magnetic separation in the bacteria liquid could be completed within 10 min by adding Ag/Fe3O4/rGO in magnetic field.Selecting Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus) as the experimental strains,the antibacterial properties of the composite was evaluated by the agar diffusion method,minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC).Ag/Fe3O4/rGO showed strong antibacterial activities against E.coli and S.aureu.The antibacterial circle diameter was 18 mm and 13 mm,the MIC was 50 mg/L and 80 mg/L,and the MBC was 30 mg/L and 50 mg/L respectively.