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1、QTRAP4000OperatorTrainingWhatisLC/MSLC:LiquidChromatographyMS:MassSpectrometeraninstrumentthatproducesionsandseparatestheminthegasphaseaccordingtotheirmass-to-chargeratio(m/z)Generatedesolvatedions(Sources)Transferionsintomassspectrometrevacuum(InterfaceRegion)Massanalyzeions(Quadr
2、upolesinvacuumcondition)Detections(Detectorinvacuumcondition)ProcesstheData(Software)ProcessNeededtoGenerateaMassSpectrumTurboVIONSOURCEHousingIonSourceProbesInterfaceFixedSprayerGeometryPlug&PlayInterchangeable TurboIonandAPCIProbesAPIAnalyticalDomainsNeutral101102103104105Molecul
3、arWeightIonicAnalytePolarityIonSprayAPCIGC/MSTurboIonSpraySource:ISVoltage-DeclustersandgeneratesionsIS-VerypHdependentforchargingofmoleculeNebulizer&TurboGas-Declustersandde-solvatesIonsTurboIonSpray(cont)ModifiersOrganicacids(e.g.formic,acetic)promoteionizationofbasiccompounds(sp
4、3N-containing)AdductFormation-Neutralcompoundscontainingnucleophiliclonepairs(sp2N,sp3O)canbeionizedbycationizationwithalkalimetalorammoniumions.RecommendedBuffers-Ammoniumformateoracetateareat(2-10mMoptimum,canseesuppressioneffectsover20mM),.1%FormicAcid,(.1%TFAOK)TurboIonSpray(co
5、nt)CompoundsThatCauseSensitivitySuppressionSaltscaninterferewithionizationandcanclustertocomplicatespectrum(butalsoaidinidentification)StrongbasesorquaternaryaminescaninterferewithpositivemodeanalytesAcids-SulfuricandTFAinterfereinnegativemodeexperiments.DONOTUSEPHOSPHATEBUFFERSNon
6、-CovalentDimersinIonSprayDimerSignal=(MW*2)+1onecauseofnon-linearityathighconcentrationsAPCIProbeHeatedNebulizer(cont.)AtmosphericPressureChemicalIonization(APCI)APCIutilizescoronadischargeAPCIisa“three”stepprocess:1)Needleathighvoltageionizesnebulizinggas(airornitrogen)formingprim
7、aryions2)Primaryionsreactimmediatelywithsolventmoleculesformingreagentions3)Reagentionsreact(byprotontransfer)withanalytemoleculesforming(M+H)+inpositiveionmodeor(M-H)-innegativeionmodeHeatedNebulizer-APCIBuffers:Buffers/modifiersnotrequiredforionizationVolatilebufferstoleratedupto
8、50mMVerypolarmodifiersmayr
