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ASTM F2605-2008e1 用体积排阻色谱与多角度光散射检测法(SEC-MALS)测定海藻酸钠的摩尔质量的标准试验方法体

作者:标准资料网 时间:2024-05-18 13:22:25  浏览:8976   来源:标准资料网
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【英文标准名称】:StandardTestMethodforDeterminingtheMolarMassofSodiumAlginatebySizeExclusionChromatographywithMulti-angleLightScatteringDetection(SEC-MALS)
【原文标准名称】:用体积排阻色谱与多角度光散射检测法(SEC-MALS)测定海藻酸钠的摩尔质量的标准试验方法体
【标准号】:ASTMF2605-2008e1
【标准状态】:现行
【国别】:美国
【发布日期】:2008
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:F04.42
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:Alginates;Sizeexclusionchromatographywithmulti-anglelightscatteringdetection(SEC-MALS);Tissueengineeredmedicalproducts(TEMPs)
【摘要】:Thecompositionandsequentialstructureofalginate,aswellasthemolarmassandmolarmassdistribution,determinesthefunctionalityofalginateinanapplication.Forinstance,thegellingpropertiesofanalginatearehighlydependentuponthecompositionandmolarmassofthepolymer.Lightscatteringisoneofveryfewmethodsavailableforthedeterminationofabsolutemolarmassandstructure,anditisapplicableoverthebroadestrangeofmolarmassesofanymethod.Combininglightscatteringdetectionwithsizeexclusionchromatography(SEC),whichsortsmoleculesaccordingtosize,givestheabilitytoanalyzepolydispersesamples,aswellasobtaininginformationonbranchingandmolecularconformation.Thismeansthatboththenumber-averageandmass-averagevaluesformolarmassandsizemaybeobtainedformostsamples.Furthermore,onehastheabilitytocalculatethedistributionsofthemolarmassesandsizes.Multi-anglelaserlightscattering(MALS)isatechniquewheremeasurementsaremadesimultaneouslyoverarangeofdifferentangles.MALSdetectioncanbeusedtoobtaininformationonmolecularsize,sincethisparameterisdeterminedbytheangularvariationofthescatteredlight.Molarmassmayinprinciplebedeterminedbydetectingscatteredlightatasinglelowangle(LALLS).However,advantageswithMALSascomparedtoLALLSare:(1)lessnoiseatlargerangles,(2)theprecisionofmeasurementsaregreatlyimprovedbydetectingatseveralangles,and(3)theabilitytodetectangularvariationallowsdeterminationofsize,branching,aggregation,andmolecularconformation.Sizeexclusionchromatographyusescolumns,whicharetypicallypackedwithpolymerparticlescontaininganetworkofuniformporesintowhichsoluteandsolventmoleculescandiffuse.Whileinthepores,moleculesareeffectivelytrappedandremovedfromtheflowofthemobilephase.Theaverageresidencetimeintheporesdependsuponthesizeofthesolutemolecules.Moleculesthatarelargerthantheaverageporesizeofthepackingareexcludedandexperiencevirtuallynoretention;theseareelutedfirst,inthevoidvolumeofthecolumn.Molecules,whichmaypenetratetheporeswillhavealargervolumeavailablefordiffusion,theywillsufferretentiondependingontheirmolecularsize,withthesmallermoleculeselutinglast.Forpolyelectrolytes,dialysisagainsttheelutionbufferhasbeensuggested,inordertoeliminateDonnan-typeartifactsinthemolarmassdeterminationbylightscattering(1,2).However,inthepresentmethod,thesizeexclusionchromatographystepprecedingthelightscatterdetectionisanefficientsubstituteforadialysisstep.ThesampleisseparatedonSECcolumnswithlargeexcessofelutionbufferfor30to40min,anditisthereforeinfullequilibriumwiththeelutionbufferwhenitreachestheMALSdetector.1.1Thistestmethodcoversthedeterminationofthemolarmassofsodiumalginateintendedforuseinbiomedicalandpharmaceuticalapplicationsaswellasintissueengineeredmedicalproducts(TEMPs)bysizeexclusionchromatographywithmulti-anglelaserlightscatteringdetection(SEC-MALS).AguideforthecharacterizationofalginatehasbeenpublishedasGuideF2064.1.2AlginateusedinTEMPsshouldbewellcharacterized,includingthemolarmassandpolydispersity(molarmassdistribution)inordertoensureuniformityandcorrectfunctionalityinthefinalproduct.Thistestmethodwillassistendusersinchoosingthecorrectalginatefortheirparticularapplication.AlginatemayhaveutilityasascaffoldormatrixmaterialforTEMPs,incellandtissueencapsulationapplications,andindrugdeliveryformulations.1.3Thevalue......
【中国标准分类号】:C10
【国际标准分类号】:11_120_10
【页数】:6P.;A4
【正文语种】:英语


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【英文标准名称】:StandardfortheFunctionalArchitectureofNextGenerationServiceOverlayNetworks
【原文标准名称】:下一代业务叠加网络的功能架构标准
【标准号】:IEEE1903-2011
【标准状态】:现行
【国别】:美国
【发布日期】:2011
【实施或试行日期】:
【发布单位】:美国电气电子工程师学会(US-IEEE)
【起草单位】:IEEE
【标准类型】:()
【标准水平】:()
【中文主题词】:体系架构(IT);电路网络;通信技术;定义(术语);设计;信息处理;因特网;因特网协议;IP;提供者;电信;使用;用户信息
【英文主题词】:Architecture(IT);Circuitnetworks;Communicationtechnology;Definitions;Design;Informationprocessing;Internet;InternetProtocol;IP;Providers;Telecommunications;Usage;Userinformation
【摘要】:
【中国标准分类号】:M11
【国际标准分类号】:35_240_99
【页数】:147P;A4
【正文语种】:英语


【英文标准名称】:Biologicalevaluationofmedicaldevices-Part3:testsforgenotoxicity,carcinogenicityandreproductivetoxicity.
【原文标准名称】:医疗设备的生物学评价.第3部分:遗传毒性、致癌性和生殖毒性试验
【标准号】:NFS99-501-3-2009
【标准状态】:现行
【国别】:法国
【发布日期】:2009-12-01
【实施或试行日期】:2009-12-18
【发布单位】:法国标准化协会(FR-AFNOR)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:生物测定;生物的;生物危害;生物试验;致癌物材料;致癌物;定义;牙科设备;牙科器械;牙科材料;评定;精密机械;基因;遗传学;基因毒性;植入物(外科);材料;医疗器械;医疗设备;医疗产品;医学科学;方法;准备;复制;生殖系统;试样;试样制备;外科设备;外科植入物;试验;毒性
【英文主题词】:Bioassay;Biological;Biologicalhazards;Biologicaltests;Carcinogenicmaterials;Carcinogens;Definitions;Dentalequipment;Dentalinstruments;Dentalmaterials;Evaluations;Finemechanics;Genes;Genetics;Genotoxicity;Implants(surgical);Materials;Medicaldevices;Medicalequipment;Medicalproducts;Medicalsciences;Methods;Preparation;Reproductions;Reproductivesystem;Samples;Specimenpreparation;Surgicalequipment;Surgicalimplants;Testing;Toxicity
【摘要】:
【中国标准分类号】:C37
【国际标准分类号】:11_100_20
【页数】:27P;A4
【正文语种】:其他



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