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1、第四节、串联质谱应用,一、碰撞诱导裂解（CAD）二、源内CAD三、IRMPD和ECD,一、碰撞诱导裂解（CAD）,API 4000 LC/MS/MS,APCI,Linear,Varian 1200 GC/MS/MS,180o,二、源内CAD,三、IRMPD和ECD,Infrared Multiphoton Dissociation: IRMPD Electron Capture Dissociation: ECD,Magnet,ESI source,capillary,ionguide,cell,Differential pumping stages,CO2 - Laser,HPLC,Setu
2、p of IRMPD,fast MS/MS coupled to HPLC,Infrared Multiphoton Dissociation (IRMPD),Hot topic at this years ASMS !,m = 1.1 ppm,m = 0 ppm,m = 0 ppm,m = 0.9 ppm,m = 1.4 ppm,m = 0.6 ppm,2,3,6s,1,4,5,6,1,3,4,6,5,SORI-CADMS/MS TIC,IRMPD MS/MS TIC,2,Infrared Multiphoton Dissociation (IRMPD),Applications for I
3、RMPD,MS/MS with HPLCNo need for pulsed gas, faster MS/MS experimentHigh throughput proteomicsRapid acquisition of MS/MS fragment information from peptides with accurate massSingly charged peptides from MALDI are often difficult to fragment by CID in FTMSGeneral Structural Characterization of Natural
4、 Products, Drug Candidates, Oligonucleotides, Other UnknownsIRMPD gives more extensive fragmentation with many compound classes,Compare IRMPD with “normal” SORI CID - Ions Present,2.0,2.5,3.0,3.5,min,1,2,3,4,5,6,IRMPD TICAcquisition rate = 1 Hz,CAD TICAcquisition rate = 0.3 Hz,Compare IRMPD with “no
5、rmal” SORI CID - Duty Cycle,200,300,400,500,600,700,800,900,1000,1100,1200,m/z,MALDI FTMS of LHRHIRMPD MS/MS of the MH+IR laser: 200ms 50% power,b2,y6,y5,y4,y3,b6,b7,b8,b4,b3,b5H2O,b4H2O,MH+,MH+-H2O,IRMPD Data Examples (2),ECD, 9 eV M+nHn+ + e- M+nH(n+1)+ + 2e- M-nHn- + e- M-nH(n-1)- + 2e- M-nHn- +
6、e- (M-nH(n-1)-)*transient + 2e- fragments + e-More energetic electrons may cause double ionization and Coulombic explosion.,Remaining +2 Parent Ion After ECD,c10,c6,c7,c8,c9,c5,C Sequence Ions in the ECD Spectrum of Substance P,c25,C21,c22,c23,c24,C15,C18,C12,C11,C10,C7,C6,z24,z23,z20,z19,z17,z16,z14,z12,z9,z5,z3,C and Z Sequence Ions in the ECD Spectrum of Melittin,
