Ag/Fe_(3)O_(4)纳米复合材料的绿色合成及其抑菌机制  

Green synthesis and antibacterial mechanism of Ag/Fe_(3)O_(4)nanocomposites

作　　者：苏添浩 刘康康 张晓东 龙秀娇 陈赛黎 曹海雷 吕健 Su Tianhao;Liu Kangkang;Zhang Xiaodong;Long Xiujiao;Chen Saili;Cao Hailei;Lv Jian(Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation,College of Resources and Environment,Fujian Agriculture and Forestry University,Fuzhou 350002)

机构地区：[1]福建农林大学资源与环境学院,福建省土壤环境健康与调控重点实验室,福州350002

出　　处：《化工新型材料》2023年第3期227-233,共7页New Chemical Materials

基　　金：福建省自然科学基金项目(2021J01121)。

摘　　要：以茶叶提取液为还原剂,采用原位还原方法绿色合成Ag/Fe_(3)O_(4)复合材料,系统表征了复合材料的形貌及组成特性,并对其抑菌性能及机制进行了深入分析。X射线衍射(XRD)、X射线光电子能谱(XPS)表征结果表明:Ag(I)被还原为Ag0;振动样品磁强计(VSM)测试表明:Ag/Fe_(3)O_(4)具有较高的饱和磁化强度;透射电镜(TEM)测试表明:所负载Ag0粒径在50~100nm之间;红外光谱(FT-IR)测试结果表明:茶叶提取液中的酚羟基起到了桥接金属元素及还原剂的作用。复合材料的抑菌研究表明,Ag/Fe_(3)O_(4)对大肠杆菌和金黄色葡萄球菌的生长均有良好的抑制效果,其最低抑菌浓度(MIC)分别为1.76μg/mL和7.04μg/mL。通过碱性磷酸酶(AKP)、核酸、蛋白质的测定,以及扫描电镜(SEM)表征,证实Ag/Fe_(3)O_(4)的接触使菌体表面结构坍塌、内陷、甚至分裂,并通过影响菌体细胞壁、细胞膜的通透性,影响其基因的表达,达到抑菌目的。Ag/Fe_(3)O_(4)nanocomposites were green synthesized by in situ reduction method using tea extract as the reducing agent,and then the morphology and compositions of the composites were systematically characterized.After that,their antibacterial properties and mechanisms were intensively studied.The reduction of Ag(I)to Ag0on the Fe_(3)O_(4)carrier was verified by X-ray powder diffraction and X-ray photoelectron spectroscopy.VSM test showed that Ag/Fe_(3)O_(4)possessed high saturation magnetization intensity.The particle size of the synthesized Ag0ranged from 50to 100nm,which demonstrated by transmission electron microscopy images.Infrared spectra exhibited that the phenolic hydroxyl groups in tea extract acted as reducing agent as well as a bridge that connecting Ag and Fe elements during the reduction process.The results of growth curve and antibacterial activity implied that Ag/Fe_(3)O_(4) had a good inhibitory effect on the growth of Escherichia coli and Staphylococcus aureus.The minimum inhibitory concentration(MIC)of Ag/Fe_(3)O_(4)composite against Escherichia coli and Staphylococcus aureus were 1.76μg/mL and 7.04μg/mL,respectively.The determination of alkaline phosphatase(AKP),nucleic acid and protein,and SEM characterization confirmed that the contact of Ag/Fe_(3)O_(4)caused the collapse,invagination and even division of the cell surface structure,and affected the permeability of cell wall and cell membrane.Consequently,the expression of the genes was strongly affected to achieve the purpose of bacteriostasis.

关 键 词：绿色合成 银 磁性纳米复合材料 抑菌机制 

分 类 号：TB333[一般工业技术—材料科学与工程]