各类质谱的优缺点
1.磁质谱
Benefits
Classical mass spectra
Very high reproducibility
Best quantitative performance of all mass spectrometer analyzers
High resolution
High nsitivity
High dynamic range
Linked scan MS/MS does not require another analyzer
High-energy CID MS/MS spectra are very reproducible
Limitations
Not well-suited for puld ionization methods (e.g. MALDI)
Usually larger and higher cost than other mass analyzers
Linked scan MS/MS gives either limited precursor lectivity with unit product-ion resolution, or unit precursor lection with poor product-ion resolution
Applications
All organic MS analysis methods
Accurate mass measurements
Quantitation Isotope ratio measurements
2.四极杆质谱
Benefits
Classical mass spectra
Good reproducibility
Relatively small and low-cost systems
• Low-energy collision-induced dissociation (CID) MS/MS spectra in triple quadrupole and hybrid mass spectrometers have efficient conversion of precursor to product
Limitations
Limited resolution
Peak heights variable as a function of mass (mass discrimination). Peak height vs. mass respon must be 'tuned'.
Not well suited for puld ionization methods
Low-energy collision-induced dissociation (CID) MS/MS spectra in triple quadrupole and
hybrid mass spectrometers depend strongly on energy, collision gas, pressure, and other factors.
Applications
Majority of benchtop GC/MS and LC/MS systems
Triple quadrupole MS/MS systems
Sector / quadrupole hybrid MS/MS systems
Quadrupole/ion trap hybrid MS/MS systems
Quadrupole/FTICR hybrid MS/MS systems
3.飞行时间质谱
Benefits
Fastest MS analyzer
Well suited for puld ionization methods (method of choice for majority of MALDI mass spectrometer systems)
High ion transmission
MS/MS information from post-source decay
Highest practical mass range of all MS analyzers
Limitations
Requires puld ionization method or ion beam switching (duty cycle is a factor)
Fast digitizers ud in TOF can have limited dynamic range
Limited precursor-ion lectivity for most MS/MS experiments
Applications
Almost all MALDI systems
Very fast GC/MS systems
4.傅立叶变换离子回旋共振质谱
Benefits
The highest recorded mass resolution of all mass spectrometers
Powerful capabilities for ion chemistry and MS/MS experiments
Well-suited for u with puld ionization methods such as MALDI
Non-destructive ion detection; ion remeasurement
Stable mass calibration in superconducting magnet FTICR systems
Limitations
Limited dynamic range
Strict low-pressure requirements mandate an external source for most analytical applicat
ions
Subject to space charge effects and ion molecule reactions
Artifacts such as harmonics and sidebands are prent in the mass spectra
Many parameters (excitation, trapping, detection conditions) compri the experiment quence that defines the quality of the mass spectrum
Generally low-energy CID, spectrum depends on collision energy, collision gas, and other parameters
Applications
Ion chemistry
High-resolution MALDI and electrospray experiments for high-mass analytes
Lar desorption for materials and surface characterization
5.离子阱质谱
Benefits
High nsitivity
Multi-stage mass spectrometry (analogous to FTICR experiments)
Compact mass analyzer
Limitations
Poor quantitation
Very poor dynamic range (can sometimes be compensated for by using automatic gain control)
Subject to space charge effects and ion molecule reactions
Collision energy not well-defined in CID MS/MS
Many parameters (excitation, trapping, detection conditions) compri the experiment quence that defines the quality of the mass spectrum
Applications
Benchtop GC/MS, LC/MS and MS/MS systems
Target compound screening
Ion chemistry
