现代仪器分析第八章质谱法_精品文档.ppt

现代仪器分析第八章质谱法_精品文档.ppt

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第八章质谱法,MassSpectroscopy（MS）,质谱仪的一般结构,真空系统,进样系统,离子检测器,数据系统,质量分析器,离子源,大气,样品,机械泵，分子涡轮泵，扩散泵，离子泵，升华泵,气体：

气相色谱仪（GC/MS）液体：

液相色谱仪（LC/MS）固体：

固体进样杆（DIP,DCI）,电子倍增器，多通道板检测器光电倍增管，阵列检测器,通常的离子化方法,电子轰击离子化EI化学电离离子化CI正化学电离离子化PCI负化学电离离子化NCI大气压力离子化API电喷雾离子化ESI大气压化学电离离子化APCI,GC/MS,LC/MS,离子化方式,分子量,非极性,极性,EI/CI,ESI,APCI,100,000,1000,离子化和碎片,离子化,硬,无碎片,有碎片,API,EI,CI,软,质量分析器,四极杆80%的台式质谱仪（3000/年）HP,PE,TMQ,Shimadzu离子阱20%的台式质谱仪（700/年）Varian,TMQ飞行时间（ToF）目前用户较少（50-60/年）Leco,Micromass,TMQ扇形磁场通常不是台式仪器,扇形磁场质量分析器,离子通过变化的磁场和电场被传输,四极质量分析器,离子阱,原理与四极杆的非常相似，离子被存储在RF和DC场中，扫描场逐出精确m/z的离子。

飞行时间质量分析器,所有离子同时启动小的离子移动速度快测量已知距离下的速度（飞行时间）,ElectronImpactIonization（EI）,e-,e-,e-,e-,e-,SamplefromGC,filament,+,+,+,+,Fragmention,QP,ElectronImpactIonization（EI）,Thermalelectrons（ca.70eV）hitmoleculesandionizethem.Amplefragmentions=amplestructuralinformationFingerprint,EIspectrumMethylstearateM.W.298,PositiveChemicalIonization（PCI）,fromgascylinder,filament,QP,CH4,CH5+C2H5+,SamplefromGC,H+,-CH4,M+1,-C2H4,PositiveChemicalIonization（PCI）,Reagentgasmoleculesareionizedfirst.Samplemoleculesareionizedmainlyby損rotontransfer?

Quasimolecularionseasilyproducedusefulformolecularweightverification.,+,PCIspectrumMethylstearateM.W.298,ComparisonofEIandPCI,EImode,PCImode,NegativeChemicalIonization（NCI）,Negativeionformationbyelectroncaptureassociativeresonancecapturedissociativeresonancecaptureion-pairproductionNegativeionformationbyion-moleculereactionsprotontransferchargeexchangenucleophilicadditionnucleophilicdisplacement,Negativeionformationbyelectroncapture（associativeresonancecapture）,MX+e-（0eV）MX-.,X:

positiveelectronaffinitypart,CH4,MX,CH4,+,CH3,+,H,CH4,CH4,CH4,e-,MX,-,质谱图的样子?

EI和CI的质谱图,m/z,0,100,%,510,511,512,m/z,0,100,%,241,213,510,242,EI,NCI,扫描50到300amu流入质谱仪的化合物,质谱图.,断裂机理,1.断裂,2.断裂,3.i断裂,4.逆Diels-Alder反应,5.Mclafferty重排,ConfigurationofGCMS,MassSpectrometer,GasChromatograph,Interface,Ionsourcebox,IonSourceDesign-Increasedionizationefficacy-,InterfaceThesampleseparatedbyGCwillbeintroducedthroughthisinterface.,FilamentIongeneratedbyfilamentwillgivetheelectronimpacttothesampletoproducethesampleionization.,Ionsourcebox,IonLens-Highionintroductiontomassanalyzer-,Thisionlensisfunctioningforeffectiveintroductiontomassanalyzer.OptimizationforadjustmentofthisionlenswillbedonebyPCautomatically.,QuadrupoleRod-MinimizelossesintransittotheQuadrupole-,MainRodSpecificiononlycanbepassedbytheelectronicfieldintoQuadrupoleRodwhichiscontrolledbyPC.,PreRod,Fromionsource,Todetector,rotarypumpturbomolecularpump（151L/sec）,turbomolecularpump（151L/sec）,rotarypump,Goodvacuumsystem-MinimizelossesintransittotheQuadrupole-,TurboMolecularPump,AircooledandoilfreeTurbomolecularPump（TMP）withlubricantimpregnatedceramicbearingsismaintenancefreeforupto25,000hours.Provideshighqualityvacuuminlessthan5mins.,Iondetection,Negativeiondetection,Positiveiondetection,GCMS-QP5050ANCIsensitivity,200fgHexachlorbenzene,NCIspectrum,Masschromatogramofm/z284,OFN（octafluoronaphthalene）NCIscanmode,OutstandingHighSensitivity,scanrangem/z60-310,0.5secinterval,200fgS/N30,GCMS-QP5050ANCIpesticidesdate3,10pgCyanophosNCImassspectrum,phosphoruspesticides10pg,ComparisonbetweenEIandNCIextractfromcabbage（pesticidesadded）,EIscanningmode,NCIscanningmode,ComparisonbetweenEIandNCIextractfromcabbage（pesticidesadded）,PrincipleofProgramedtemperaturevaporize（PTV）,PTV,100C,split,MS,50-250C,Solventwillbevaporizedandexhausted.Samplewillbeconcentrated.,OptimizationofPTVconditions,SelectionofpackingmaterialsTenaxGC20%OV-120%OV-1720%Dexil300ShincarbonACarbopackCTraptemperatureDesorptiontemperatureTemperatureprogram,Very-Large-VolumeInjectionusingPTVEffectofTemperatureonTrapefficiency,Very-Large-VolumeInjectionusingPTVTemperatureandSplitratioProgram,Very-Large-VolumeInjectionusingPTV2ppbeachPesticidesinn-hexane1000uLInjection,AnalyticalConditionsGC17AVer.2DB130mX0.25mm50C（4）-160C-280C20C/min5C/minPTV70C

（1）-100C

（1）-280C30C/min250C/minWiderangeFTD1pA280CCarriergasHe150kPaPrecolumnTenaxGC,FeaturesofGCMSQP-5050A,OutstandinghighsensitivityExtendedmassrangeupto900amuVersatileMode-EI/PCI/NCI/DICompactDesignEasyOperationusingWindowsSoftwareEasytuning-PFTBAbuiltinstandardEasymaintenance,AnalysisofCoconutoil,MSSpectrumofC48,DIoption,Thedirectinletoptionallowslessvolatileorthermallylabilesamplestobedirectlyintroducedintothemassspectrometer.MixturesofcompoundswhichhavedifferentboilingpointscanbepositivelyidentifiedbyprogrammingtheDIprobetemperature.,Applicationusingdirectinletprobe,Front-openionchambersystem-easymaintenance-,DualFilamentsSystem-easymaintenance-,LCMS-QP8000Validation,ProductivityandMassDetection,Whatkindofbenefits