Interpretation of CID Mass Spectra:
Course Description:
A two-day "advanced" course. The course will cover
generation and interpretation of CID mass spectra generated from
positive and negative ions formed from APCI or electrospray. Topics
covered will include formation of ions, variables in CID mass
spectra under tandem MS (triple quadrupoke, ion trap) and API
transport CID, interpretation of both the molecular ion and common
molecular adduct ions and the product ion formed from these species
after CID. The interpretation of the product ion mass spectra
will be broken down into distinctive fragmentation mechanisms
to aid the student to develop a systematic approach towards spectral
enterpretation. All topics will be re-emphasized with problem
sets.
Day 1 Outline:
Generating CID Spectra
- API transport CID
- Tandem MS
- Comarison of trap, triple and high-energy CID spectra
Interpretation of API Mass Spectra:
- Identifying the molecular ion
- Using isotope abundances to gain information
- Nitrogen rule
- Indentifying other adduct ions, dimers and multiply charged
species
Interpretation of Positive ion CID Spectra:
- Variability of CID
- Stability of ions and neutrals
- Charge retention vs. charge migration fragmentation
- Single bond cleavages
- Cyclization reactions
- Multiple bond cleavages
- Rerrangement reactions
- Charge remote fragmentation
- Problem sets
Day 2 Outline:
Interpretation of Negative ion Cid Spectra:
- Stability of negative ions
- Charge retention vs. charge migration fragmentation
- Single bond cleavages
- Cyclization reactions
- Multiple bond cleavages
- rerrangement reactions
- Charge remote fragmentation
- Problem sets
Interpretation of CID mass spectra generated from ions other
than [M+H]+ or [M-H]-
- Interpretation of CID mass spectra from alkali metal cations
- Interpretation of CID mass spectra from halogen anions
- Interpretation of CID mass spectra from fultiply charged ions
(anions and cations)
Techniques and Tools to help with CID Interpretation:
- Isotopic labeling
- Hydrogen-deuterium exchange
- Using MSn
- CID libraries and their generation
- Commercial softward tools
Problems:
- Real world problems in the areas of pharmaceuticals, biochemical,
clinical, industrial and forensic and environmental that aid
in the development of the students systematic approach to interpretation
of CID mass spectra.
Summary/Concluding Remarks:
- Problem Set Reviewing Material Covered in Course
Student Profile:
- This course is designed for the student who has completed
an LC/MS short course or who has working knowledge of LC/MS
and wants to improve their qualitative interpretation skills
for problem solving in LC/MS.