Thermally assisted collision-induced dissociation in a quadrupole ion trap mass spectrometer.

Thermally assisted collision-induced dissociation (TA-CID) provides increased dissociation in comparison with CID performed at ambient temperature in a quadrupole ion trap mass spectrometer. Heating the bath/collision gas during CID increases the initial internal energy of the ions and reduces the collisional cooling rate. Thus, using the same CID parameters, the parent ion can be activated to higher levels of internal energy, increasing the efficiency of dissociation and the number of dissociation pathways.

Determination of cooling rates in a quadrupole ion trap.

Collisional cooling rates of infrared excited ions are measured in a quadrupole ion trap (QIT) mass spectrometer at different combinations of temperature and pressure. Measurements are carried out by monitoring fragmentation efficiency of leucine enkephalin as a function of irradiation time by an infrared laser after a short excitation and incrementally increasing cooling periods. Cooling rates are observed to be directly related to bath gas pressure and inversely related to bath gas temperature.

Tandem mass spectrometry in quadrupole ion trap and ion cyclotron resonance mass spectrometers.

Instruments that trap ions in a magnetic and/or electric field play a very important role in the analysis of biomolecules. The two predominant instruments in the category of trapping instrument are the quadrupole ion trap mass spectrometer (QIT-MS) and the ion cyclotron resonance (ICR) MS. The latter is also commonly called Fourier transform MS (FT-MS).