CID and HCD
Definition
Collision-induced dissociation. The precursor is accelerated and collides with a neutral gas (nitrogen, argon, helium) in the collision cell. Internal energy converts to bond-cleavage. Higher-energy collisional dissociation (HCD) on Orbitrap instruments uses a dedicated cell at higher energy and gives more reproducible fragmentation than ion-trap CID.
Related terms
- Accurate Mass and Mass Defect
- On a Q-TOF or Orbitrap, the measured m/z is reported to four decimal places at parts-per-million accuracy. The deviation from the nominal...
- Deuterated Internal Standard
- An isotopologue of the analyte where two to five hydrogens are replaced by deuterium. Same chromatographic and ionisation behaviour, slightly higher mass....
- MRM (Multiple Reaction Monitoring)
- A targeted MS/MS scan mode on a triple quadrupole that monitors specific precursor-to-product ion transitions, with two transitions per analyte (quantifier and...
- Quantifier and Qualifier Transitions
- The most intense MRM transition is the quantifier and is used for the concentration calculation. The second (and sometimes third) transition is...
- Tandem MS (MS/MS)
- Two stages of mass selection in series with a fragmentation step in between. The first stage selects a precursor ion, a collision...
Explained in
- Tandem Mass Spectrometry (MS/MS) and Spectral InterpretationCollision-induced dissociation. The precursor is accelerated and collides with a neutral gas (nitrogen, argon, helium) in the collision cell. Internal energy c...