石墨烯基纳米银复合抗菌材料的制备及其结构性能研究.docx
石墨烯基纳米银复合抗菌材料的制备及其结构性能研究2012届暨南大学硕士学位论文摘要纳米银具有安全无毒,高效、广谱和长效抗菌性,无耐药性的特点，已开始应用在医疗卫生、生态环境、建筑厨卫、电子电器和日用品等领域。但是其价格高、难分散和易氧化变色的缺点限制了其广泛应用。石墨烯是单原子厚度的二维石墨碳材料,具有高比表面积、突出的导热性能和力学性能、非凡的电子传递性能等一系列优异性质，是功能材料的理想载体。因此,本文先以水溶性有机物修饰还原氧化石墨烯(rGO)得到水溶性还原氧化石墨烯载体,然后将纳米银负载于其上获得石墨烯基纳米银复合抗菌材料,研究了其制备、结构和性能。首先,制备了采用聚乙烯亚胺修饰的石墨烯基纳米银复合抗菌材料(AgNP/PEbrGO),并通过FTIR、XRD>XPS>TEM>AFM>Zeta电位、ICP和紫外可见光谱进行表征，同时分析了抗菌活性、细胞毒性和生物相容性。结果表明：聚乙烯亚胺通过0C-NH连接在石墨烯上，聚乙烯亚胺修饰石墨烯厚度约0.6nm;AgNP在AgNP/PEI-rGO表面的分布比较均匀,纳米银的质量分数为4.2%,其粒径为5-15nm,Zeta电位为-46.7mV;在超纯水中浸泡20天后，聚乙烯毗咯烷+酮修饰的纳米银(PVPAgNP)中Ag的释放率为90.7%,而AgNPPEbrGO中+Ag的释放率明显要慢,为72.5%;在无光或有光环境下储存7天,PVPAgNP聚集作用显著,而AgNP/PEI-rGO没有发生明显变化;与PvP/AgNP相比，AgNP/PEI-rGO具有更高的抗菌活性和生物相容性,更低的生物毒性。其次,制备了采用蔡磺酸钠修饰的石墨烯基纳米银复合抗菌材料(AgNP/NArGO),并通过XRD、XPS、TEM>AFM>Zeta电位、紫外可见光谱和荧光光谱进行表征，同时分析了抗菌活性、细胞毒性和生物相容性。发现AgNP/NA-rGO中纳米银的质量分数为3.6%,在水中的溶解度可以达到1.1mgmL,Zeta电位为-42.3mV,所形成的悬浮液可稳定存在水溶液中3个月以上而+不沉淀;NArGO比聚乙烯此咯烷酮更有效阻止Ag氧化,达到缓释效果;其与大肠杆菌(E.coli)和金黄色葡萄球菌(S.aureus)接触6h后的抗菌率分别是92.4%、96.9%;它是一种带有轻微细胞毒性以及生物相容性较好的纳米复合材料。关键词:石墨烯、纳米银、制备、抗菌活性、稳定性I2012届暨南大学硕土学位论文AbstractWiththeexcellentcharacteristicsofsafetyandnontoxicity,high-efficiency,broad-spectrum,andlong-termantibacterialactivity,silvernanoparticlesAgNPhasbeenappliedinthefieldofmedicalcare,eco-environment,architecture,kitchenandtoilet,electronics,anddailyproducts,etc.However,shortcomingslikeitshighprice,difficultyindispersion,andthetendencytobeoxidizedanddiscolorationarestillrestrictionsforitswiderrangeofapplications.Grapheneisasingle-atom-thicktwo-dimensionalgraphiticcarbonmaterial.Manysuperiorpropertiesofit,suchashighspecificsurfacearea,excellentthermalconductivityandextraordinarymechanicalandelectrontransportationproperties,etc.makegraphenetobeaperfectsubstrateforfunctionalmaterials.Therefore,inthisthesis,weusedwater-solubleorganiccompoundstomodifyreductiongrapheneoxiderGOtoobtainthewater-solublerGOsubstrate,andthenweloadedAgNPonittoprepareanrG0-AgNPcompositeantibacterialmaterial.StructuresandpreparationprocessesareinvestigatedandpropertiesarecharacterizedinthisthesisFirst,wepreparedsilvernanoparticles/polyethyIeneiminePEI-reductiongrapheneoxideAgNP/PEI-rGOcompositeantibacterialmaterialwhichismodifiedbypolyethyIeneimine.XRD,FTIR,XPS,TEM,AFM,Zeta-potential,ICPandUV-VISareusedtocharacterizethepropertiesofthematerial,andtheantibacterialactivity,celltoxicityandbiocompatibilityarealsoanalyzed.ResultsshowthatPEIhasbeenattachedtotherGOthrogh0C-NH,andthethicknessofrGOmodifiedbyPEIwas0.6nm.Inaddition,AgNPhavebeenloadedonthefunctionalizedrGOuniformlywiththediameterdistributedin5-15nm,andtheZeta-potentialis-46.7mVComparedwiththereleaserateofAgNPmodifiedbypolyvinylpyrro1idonePVPwas90.7%,thereleaserateofAgNPinAgNPPEI-rGOwasslower,andjustwas72.5%,inultrapurewaterafter20days.Afterbeingstoredindarkornaturelightlevelfor7days,PVP/AgNPaggregatedsignificantly,butAgNPPEI-rGOdidnotchangedistinctively.ComparedwithPVP/AgNP,AgNP/PEI-rGOhasthehigherantibacterialactivityandbiocompatibility,lowerbiologicaltoxicityII2012届暨南大学硕士学位论文Andthen,wepreparedsodiumnaphthaleneSulfonateNA/reductiongrapheneoxide-SilvernanoparticlesAgNPNA-rGOcompositeantibacterialmaterialwhichismodifiedby1-sodiumnaphthalenesulfonate.XRD,XPS,TEM,AFM,Zeta-potential,ICP,UV-VISandfluorescencespetraareusedtocharacterizethepropertiesofthematerial,andtheantibacterialactivity,celltoxicityandbiocompatibilityarealsoanalyzed.ResultsshowthatcontentofAgNPinthecompositematerialis3.6%,solubilityinthewatercouldreach1.1mgmL,andtheZeta-potentialis-42.3mV.Inaddition,thesuspensionformedbythismaterialcouldkeepstableintheaqueouussolutionformorethan3monthswithoutdeposition.ComparedwithPolyvinylpyrrolidonePVP,NA-rGOcouldpreventAgparticlesfromoxidationeffectively,whichleadstoabettersustained-releaseeffect;Theantibacterialratecouldreach92.4%and96.9%aftercontactingwithE.coliandS.aureusrespectivelyfor6h;Thiscompositenano-materialisprovedtohaveagoodbiocompatibilityandjustslightcelltoxicityKeyWords:reductiongrapheneoxiderGO,silvernanoparticlesAgNP,preparation,antibacterialactivity,StabilityIII2012届暨南大学硕士学位论文目录摘要IAbstractII第一章绪论11.1 石墨烯.11.1.1 石墨烯概述.11.1. 2石墨烯在生物材料领域的应用.11. 1.2.1石墨烯在纳米载药体系中的应用.11.1. 2.2石墨烯在生物检测中的应用.21. 1.3石墨烯及其功能化产物的生物学评价.31.1. 3.1石墨烯及其功能化产物在对微生物的作用.31.1.3.2石墨烯及其功能化产物对人体细胞的生物学评价.41.2抗菌材料.51.2.1抗菌材料概述51.2.1.1无机抗菌材料.51.2.1.2有机抗菌材料.61.2.1.3天然抗菌材料.71.2.1.4其它抗菌剂.71.2.2纳米银抗菌材料.71.2.2.1纳米银的合成.71.2.2.2纳米银抗菌的作用机理91.2.3纳米银无机复合抗菌材料.材1.3本论文的选题意义、研究内容和创新点.111.3.1选题意义111.3.2研究内容121.3.3创新点.12第二章聚乙烯亚胺修饰的石墨烯基纳米银复合抗菌材料的制备及表征.142.1前言.142.2试剂和仪器.142.2.1试剂.142.2.2仪器与设备.152.2.3表征设备162.3实验部分.162.3.1氧化石墨(GO)的合成.162.3.2AgNP/PEI-rGO复合抗菌材料的构建172.3.2.1AgNP/PEI-rGO的合成.172.3.2.2PVP/AgNP的合成.182.3.3抗菌实验.182.3.3.1营养肉汤的配制.182.3.3.2营养琼脂的配制.182.3.3.3杀菌率试验182.3.4细胞毒性实验.182.4结果与讨论.192.4.1X射线衍射(XRD)分析19IV2012届暨南大学硕士学位论文2.4.2傅里叶变换红外光谱(FTIR)分析.21
