经典生物质谱课件

电喷雾离子化技术
(1).Electrospray Ionization (ESI)
ESI Macroview
History of Electrospray Ionization
• Malcolm Dole demonstrated the production of intact oligomers of polystyrene up to MW 500,000
2) uses laser light and a solid matrix.
3)functions of matrix: *absorb the laser light energy to vaporize the matrix and sample; *to minimize sample damage; *facilitate the ionization of samples;
Francis William Aston 1922 Nobel Prize for Chemistry "for his discovery, by means of his mass spectrograph, of isotopes, in a large number of non-radioactive elements, and for his enunciation of the whole-number rule"
Unit 2
Ionization Techniques(3)
Key notes:
1)Sample is delivered as a gas ;(involving in thermal desorption or “boiling off” the sample from the probe) 2)limited mass range ;(due to the thermal desorption (volatility) requirement) 3)principal problems in analysis of large biomolecules: difficult to volatilize(nonvolatile),thermal decomposition,excessive fragments(in many cases);
MALDI matrices
O OH
O OH OH HO
O
OH
N
MeO
OH OH
OMe
4-hydroxy-cyanocinnamic acid (“alphacyano” or 4HCCA) peptides
2,5-dihydroxybenzoic acid (DHB) peptides and proteins
Joseph John Thomson 1906 Nobel Prize for Physics "in recognition of the great merits of his theoretical and experimental investigations on the conduction of electricity by gases"
Pre-Separation
Ion Source
Mass Analyzer
Ion Detector
Liquid Chromatography
Time-of-Flight (TOF) Quadrupole TOF (QTOF) Ion Trap (IT) Fourier TransformIon Cyclotron Resonance (FT-ICR)
Chapter 1
Ion Sources and Sample Introduction
Sample Introduction
Unit 1
methods for sample introduction:
*use of insert probe; *capillary infusion; including(in fact): GC,LC,Syringe pump,needle ,etc.
identity of a molecule, but it can be used for much more……
Definition
An analytical device that determines the molecular weight of chemical components(and obtains structural information) by separating molecular(and product) ions according to their m/z;
Unit 2
Ionization Techniques(2)
1.ElectBiblioteka Baiduon Ionization,EI
use electron with certain energy impact on the sample and make them ionized.(electron impact)
Electron Ionization,EI
• Post-translational modifications • Molecular interactions • Shape • Sequence • Physical dimensions A simple measurement of mass is used to confirm the • etc...
3,5-dimethoxy-4hydroxycinnamic acid (sinapinic acid) proteins
matrices for 337 nm irradiation
MALDI
• • 337 nm irradiation is provided by a nitrogen (N2) laser The target plate is inserted into the high vacuum region of the source and the sample is irradiated with a laser pulse. The matrix absorbs the laser energy and transfers energy to the analyte molecule. The molecules are desorbed and ionized during this stage of the process. MALDI is most commonly interfaced to a time-of-flight (TOF) mass spectrometer.
能使物质粒子离子化并根据其质荷比（m/z）不同， 通过适当的电场、 磁场将它们按空间、时间先后 或者轨道稳定与否进行分离并检测强度后进行物 质分析的仪器。质谱的重要特点之一是检测物质 的离子的质/荷比。
2 质谱仪技术及其发展 The Five Mass Spectrometry Nobel Prize Pioneers
Mass Spectrometry for Biotechnology
1 质谱仪的概念？
Mass Spectrometry:
A method to “weigh” molecules
Other information can be inferred from a weight measurement.
ionization source(ion production); mass analyzer(ion separation); ion detector(ion detection);
Preface and Introduction(3)
Mass Spectrometer for Proteomics
Wolfgang Paul 1989 Nobel Prize for Physics "for the development of the ion trap technique"
John Bennet Fenn 2002 Nobel Prize for Chemistry "for the development of soft desorption ionisation methods (ESI) for mass spectrometric analyses of biological macromolecules"
Koichi Tanaka 2002 Nobel Prize for Chemistry "for the development of soft desorption ionisation methods (MALDI) for mass spectrometric analyses of biological macromolecules"
•
• Laser
Protein/Peptide
Time of Flight Mass Spect Matrix
Unit 2
Ionization Techniques(7)
Unit 2
Ionization Techniques(8)
4.Electrospray Ionization
1)basic principle produce gaseous ionized molecules from a liquid solution by means of “spray”.
Unit 2
Ionization Techniques(1)
Most common ionization methods:
*electron ionization,EI *fast atom/ion bombardment,FAB *matrix-assisted laser desorption/ionization,MALDI *electrospray ionization,ESI
Unit 2
Ionization Techniques(5)
Unit 2
Ionization Techniques(6)
3、Matrix-Assisted Laser Desorption/Ionization,(MALDI)
1)permit the analysis of high-molecular-weight compounds (and heterogeneous samples) with high sensitivity.
Unit 2
Ionization Techniques(4)
2.Fast Atom/ion Bombardment(FAB)
1)use a high-energy beam of Xe atoms,Cs ions,or massive glycerol-NH4+ clusters to sputter the sample and matrix from the probe surface into the gas phase. 2)The sample may be already charged or it may become charged through reactions with surrounding molecules or ions. 3)The ionization reaction primarily make sample protonized and form MH+.
Preface and Introduction(2)
3.Definition and basic components:
1)An analytical device that determines the molecular weight of chemical components(and obtains structural information) by separating molecular(and product) ions according to their m/z; 2)Consists of three components: