Bruker Ultraflex II TOF/TOF (April 2005)
Hybrid quadrupole-time of flight mass spectrometer, or Q-TOF. Electrospray and nanospray sources with variable in-source pressure, MALDI source.
Principle of operation
Matrix-Assisted Laser Desorption Ionization (MALDI) consists in ion generation and desorption of analytes embedded in a solid matrix by using Laser irradiation. In MS mode, the ions are all given the same kinetic energy, and the time of flight (TOF) depends on the mass of the analyte. Only fragments formed in source (in-source decay, or ISD) are detectable. In MS/MS mode (illustrated), a LIFT cell is inserted in the ion flight path, which selects a parent ion and its fragments formed after the source (post-source decay, or PSD) on the basis of their flight time in the first TOF region. The parent and fragment ions are then re-accelerated, and therefore travel with different velocities according to their masses, and are focused on the detector after passing through the reflectron.
What do we use this instrument for?
High-throughput proteomics analyses. LC-MALDI coupling for the analysis of small molecules (i.e., phycotoxins) and for proteomics. Fundamental studies on in-source decay and post-source decay mechanisms. Application of in-source decay in structural proteomics.