1、現(xiàn)代儀器分析第八章質(zhì)譜法通常的離子化方法通常的離子化方法電子轟擊離子化電子轟擊離子化 EI化學電離離子化化學電離離子化CI 正化學電離離子化PCI 負化學電離離子化NCI大氣壓力離子化大氣壓力離子化API 電噴霧離子化ESI 大氣壓化學電離離子化APCIGC/MSLC/MS離子化方式離子化方式分子量非極性極性EI/CIESIAPCI100,0001000離子化和碎片離子化和碎片離子化離子化硬硬無碎片有碎片APIEICI軟軟質(zhì)量分析器質(zhì)量分析器 四極桿四極桿 80% 的臺式質(zhì)譜儀 (3000/年) HP, PE, TMQ, Shimadzu 離子阱離子阱 20%的臺式質(zhì)譜儀 (700/年) Va

2、rian, TMQ 飛行時間飛行時間 (ToF) 目前用戶較少 (50-60/年) Leco, Micromass, TMQ 扇形磁場扇形磁場 通常不是臺式儀器zmVBzemBVRBevRmvFZeVmvEk14402221扇形磁場質(zhì)量分析器扇形磁場質(zhì)量分析器+離子通過變化的磁場和電場被傳輸四極質(zhì)量分析器四極質(zhì)量分析器+離子阱離子阱 原理與四極桿的非原理與四極桿的非常相似，離子被存儲常相似，離子被存儲在在RF和和DC場中，掃場中，掃描場逐出精確描場逐出精確m/z的的離子。離子。飛行時間質(zhì)量分析器飛行時間質(zhì)量分析器+Electron Impact Ionization (EI)e-e-e-e-e

3、-Sample from GCfilament+Fragment ionQPElectron Impact Ionization (EI) Thermal electrons (ca. 70 eV) hit molecules and ionize them. Ample fragment ions = ample structural information Finger printEI spectrumMethylstearate M.W. 298Positive Chemical Ionization (PCI)from gas cylinderfilamente-e-e-e-e-QPC

4、H4 CH5+C2H5+Sample from GCH+-CH4M+1-C2H4Positive Chemical Ionization (PCI) Reagent gas molecules are ionized first. Sample molecules are ionized mainly by 損損roton transfer? Quasi molecular ions easily produced useful for molecular weight verification. +PCI spectrumMethylstearate M.W. 298Comparison o

5、f EI and PCIEI modePCI modeFragmentMolecular weightNegative Chemical Ionization (NCI) Negative ion formation by electron capture associative resonance capture dissociative resonance capture ion-pair production Negative ion formation by ion-molecule reactions proton transfer charge exchange nucleophi

6、lic addition nucleophilic displacementNegative ion formation by electron capture (associative resonance capture) MX + e- (0 eV) MX-.X: positive electron affinity partCH4e-MXCH4+CH3+HCH4CH4CH4e-MX- 質(zhì)譜圖的樣子質(zhì)譜圖的樣子?EI和和CI的質(zhì)譜圖的質(zhì)譜圖50100150200250300350400450500550m/z0100%510511512501001502002503003504004505

7、00550m/z0100%241213510242EIOOOC F3CF3C H3NCI掃描掃描50到到300amu流入質(zhì)流入質(zhì)譜儀的化合物譜儀的化合物質(zhì)譜圖質(zhì)譜圖.60801001201401601802002202402602803000100%240241斷裂機理CH3C+CH3CH3CH2CH3CH3C+CH3CH3+CH2CH31.斷裂 2. 斷裂RRY+RY+RRCH+CH2CH2CH2+R+CCH+RCH+CH2+ 3. i 斷裂 RY+R1R+YR1CH3O+CH3CH3O+CH2+CH3CH3CH2+CH3O+i4. 逆 Diels-Alder 反應+ 。CH2+CH2+CH

8、2CH25. Mclafferty 重排 OO+CH3HCH2CH2+OH+CH3OConfiguration of GCMSMass SpectrometerGas ChromatographInterfaceIon source box Ion Source Design- Increased ionization efficacy -Interface The sample separated by GC will be introduced through this interface. FilamentIon generated by filament will give the e

9、lectron impact to the sample to produce the sample ionization.Ion source box Ion Lens- High ion introduction to mass analyzer - This ion lens is functioning for effective introduction to mass analyzer. Optimization for adjustment of this ion lens will be done by PC automatically. Quadrupole Rod - Mi

10、nimize losses in transit to the Quadrupole -Main RodSpecific ion only can be passed by the electronic field into Quadrupole Rod which is controlled by PC.Pre RodFrom ion sourceTo detectorvrotary pumpvturbo molecular pump (151 L/sec)turbo molecular pump(151 L/sec)rotary pumpGood vacuum system- Minimi

11、ze losses in transit to the Quadrupole - Turbo Molecular Pump vAir cooled and oil free Turbomolecular Pump (TMP) with lubricant impregnated ceramic bearings is maintenance free for up to 25,000 hours.vProvides high quality vacuum in less than 5 mins.Ion detection +7.5kV-+e-0.73.0kVAMP-7.5KV+e-0.73.0

12、kVAMPe-Negative ion detectionPositive ion detectionGCMS-QP5050A NCI sensitivity 200fg HexachlorbenzeneNCI spectrum Mass chromatogram of m/z284OFN (octafluoronaphthalene) NCI scan modeOutstanding High Sensitivityscan range m/z 60-310, 0.5sec interval200fgS/N 30 GCMS-QP5050A NCI pesticides date 310pg

13、Cyanophos NCI mass spectrumphosphorus pesticides 10pgComparison between EI and NCI extract from cabbage (pesticides added)EI scanning modeNCI scanning modeComparison between EI and NCI extract from cabbage (pesticides added)Principle of Programed temperature vaporize (PTV)PTV 100CsplitMS50-250CSolve

14、nt will be vaporized and exhausted.Sample will be concentrated.Optimization of PTV conditions Selection of packing materials Tenax GC 20% OV-1 20% OV-17 20% Dexil 300 Shincarbon A Carbopack C Trap temperature Desorption temperature Temperature programVery-Large-Volume Injection using PTV Effect of T

15、emperature on Trap efficiencyVery-Large-Volume Injection using PTV Temperature and Split ratio ProgramVery-Large-Volume Injection using PTV 2ppb each Pesticides in n-hexane 1000 uL InjectionAnalytical ConditionsGC17A Ver.2DB1 30mX0.25mm50C(4)-160C-280C 20C/min 5C/minPTV70C(1)-100C(1)-280C 30C/min 25

16、0C/minWide range FTD 1pA 280CCarrier gas He 150kPaPrecolumn Tenax GCFeatures of GCMS QP-5050AvOutstanding high sensitivity vExtended mass range up to 900 amuvVersatile Mode - EI / PCI / NCI /DI vCompact DesignvEasy Operation using Windows SoftwarevEasy tuning - PFTBA built in standardvEasy maintenan

17、ceAnalysis of Coconut oilMS Spectrum of C48DI optionThe direct inlet option allows less volatile or thermally labile samples to be directly introduced into the mass spectrometer. Mixtures of compounds which have different boiling points can be positively identified by programming the DI probe temper

18、ature.Application using direct inlet probeFront-open ion chamber system- easy maintenance - Dual Filaments System - easy maintenance - What kind of benefits LC/MS users can get ? Selective quantitative capability M/ZM/ZM/ZWhat kind of benefits LC/MS users can get ? Powerful qualitative capability HP

19、LCMSQP-8000 is LC/MS with API interfacewhich is designed to be a routine LC detector in our new VP series HPLC system.LCMS InterfaceCurved Desolvation Line(CDL)(CDL)DeflectorProbeSpray ChamberSkimmerLens Stack RP TMP1 TMP2Quadru poleAPI Spray ChamberAPI Spray ChamberESI Probe(Easy to change to APCI

20、Probe)API ProbeESI and APCI probes are included as standard. They can be applied to various kinds of samples. All you have to do to switch the ionization method is to change the prove.APCI probeESI ProbeMobile phase, LC flow rate and Nebulizer flow rate slightly influence spray condition. You can ad

21、just the probe position to the best for each condition.The APCI probe contains corona discharge needle. So no need to change the API spray chamber.Easy MaintenanceSkimmer Lens stack accessSpray Chamber AccessYou can pick it up from upper side without any tools.You can remove the spray chamber from t

22、he front side.It will be easy to wash this part after analysis.Standard Syringe PumpSyringe fordirect sample injectionSyringe for standard sample of calibration LCMS ApplicationMass Separation Column : STR ODS-II(2.0mmI.D.x150mm)Mobile phase:65%acetonitrile-water containing 0.1%formic acid ,0.2ml/mi

23、nMaltoseTIC387225195GlucoseXyloseOOOHOH2CHOHOOHHOH2CHOOHOHOHOH2CHOHOOHOHOH3CHOHOOHOHAnalysis of macrolide antibioticsUV 210nmMDMSIMSPM-I,IISPM-IIIOMDH EMMDMSummarywLCMS-QP8000 is a Compact Bench Top Liquid Chromatograph with high performanceswEasy Operation and Maintenance using CLASS-8000 software

24、vSelf diagnostic functionsvUser login and security defined by access levels.vOLE custom report generation wAffordable price 質(zhì)譜圖和色譜圖質(zhì)譜圖和色譜圖?如果我們注意這個區(qū)域如果我們注意這個區(qū)域.色譜圖色譜圖?1.251.501.752.002.252.502.753.003.25Time50100%TIC在此的細微觀察是由許在此的細微觀察是由許多點組成的多點組成的.色譜圖色譜圖 - 放大放大2.122.142.162.182.202.222.242.262.28Time

25、78100%TIC每個點相對于質(zhì)量分析器每個點相對于質(zhì)量分析器的一個掃描的一個掃描(質(zhì)譜圖質(zhì)譜圖).60801001201401601802002202402602803000100%240241質(zhì)譜圖質(zhì)譜圖 每個點有一張唯一的每個點有一張唯一的質(zhì)譜圖質(zhì)譜圖色譜圖上的質(zhì)譜圖色譜圖上的質(zhì)譜圖數(shù)據(jù)觀察數(shù)據(jù)觀察 - 色譜圖色譜圖樣品運行中的每秒我們可獲得一張樣品運行中的每秒我們可獲得一張或數(shù)張質(zhì)譜圖或數(shù)張質(zhì)譜圖通常是把檢測到的離子疊加在一起通常是把檢測到的離子疊加在一起獲得一個唯一的總的數(shù)值獲得一個唯一的總的數(shù)值這些總的數(shù)值然后排列在一起這些總的數(shù)值然后排列在一起(點對點對點點)產(chǎn)生一個類似的色譜圖

26、產(chǎn)生一個類似的色譜圖 (TIC).每次掃描加和所有的離每次掃描加和所有的離子得到子得到.總離子色譜圖總離子色譜圖 (TIC)數(shù)據(jù)觀察數(shù)據(jù)觀察 - 色譜圖色譜圖我們也能顯示某一張質(zhì)譜圖我們也能顯示某一張質(zhì)譜圖這讓我們一個化合物的信息這讓我們一個化合物的信息質(zhì)譜圖質(zhì)譜圖質(zhì)量色譜圖和質(zhì)量色譜圖和TICTICMass 2401.401.601.802.002.202.402.602.803.00Time0100%0100%240.271.41e5TIC4.67e5消除背景的影響消除背景的影響增加信噪比增加信噪比分離共流出物峰分離共流出物峰數(shù)據(jù)觀察數(shù)據(jù)觀察 - 選擇離子色譜圖選擇離子色譜圖TIC圖上顯示

27、的兩個接近的流圖上顯示的兩個接近的流出峰，但每個峰是具有不同出峰，但每個峰是具有不同質(zhì)譜指紋的不同化合物質(zhì)譜指紋的不同化合物.數(shù)據(jù)觀察數(shù)據(jù)觀察 -選擇離子色譜圖選擇離子色譜圖11.0012.00Time0100%TIC1.57e5數(shù)據(jù)觀察數(shù)據(jù)觀察 -選擇離子色譜圖選擇離子色譜圖100200300400500600m/z0100%254.2194.2507.3334.3399.7100200300400500600m/z0100%194.2580.4402.2226.2460.211.0012.00Time0100%TIC1.57e5分離共流出物峰分離共流出物峰10.5011.0011.5012

28、.0012.50Time0100%0100%0100%254.235.81e4194.206.14e4TIC1.57e5質(zhì)量質(zhì)量254質(zhì)量質(zhì)量 194TIC選擇離子色譜圖選擇離子色譜圖 提取出離子給出更好的信噪比提取出離子給出更好的信噪比 消除背景影響 分離共流出物峰 提取出離子也能用于提取出離子也能用于: 峰的跟蹤峰的跟蹤準確定量準確定量峰跟蹤的實例峰跟蹤的實例0100%TIC2.21e61.002.003.004.005.006.00Time0.525.653.823.251.672.005.594.954.255.725.81爆炸混合物的爆炸混合物的TIC哪一個是哪一個是HMX?HMX的

29、質(zhì)譜圖的質(zhì)譜圖峰跟蹤峰跟蹤406080100120140160180200220240260m/z0100%8472596911389106237131205158分子離子峰分子離子峰峰跟蹤峰跟蹤質(zhì)量色譜圖質(zhì)量色譜圖 m/z 237TIC1.002.003.004.005.006.007.008.009.00Time0100%0100%2.000.525.653.823.251.672.004.954.255.81分離相鄰峰的能力分離相鄰峰的能力分子離子M+H+M.+M-H-分辨率FWHM10% 峰谷m/MM+H+m/zintensity質(zhì)譜分辨率質(zhì)譜分辨率復合技術復合技術 GC/MS 氣相色

30、譜氣相色譜 - 質(zhì)譜質(zhì)譜 LC/MS 液相色譜液相色譜 - 質(zhì)譜質(zhì)譜 MS/MS 質(zhì)譜質(zhì)譜 - 質(zhì)譜質(zhì)譜MS-MS方法方法MS 1MS 2固定掃描子離子掃描固定母離子掃描掃描中性丟失固定固定選擇離子監(jiān)測結(jié)果結(jié)果MSn50100150200250300350m/z0100%2842821421077124921417725328850100150200250m/z0100%50100150200250m/z0100%50100150200250m/z0100%碎片碎片的碎片的碎片的碎片的碎片.靈敏度靈敏度? 四極桿質(zhì)譜儀如四極桿質(zhì)譜儀如TRACE MS和和AQA在在全掃描模式下能分析到低于全掃描模式下能分析到低于pg