290 likes | 922 Views
FT-ICR MS. Fourier transform ion cyclotron resonance Mass spectrometer. Dr. Alan G. Marshall. Invented in 1974 (The University of British Columbia) Ohio State University Florida State University (Center for Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory)
E N D
FT-ICR MS Fourier transform ion cyclotron resonance Mass spectrometer
Dr. Alan G. Marshall • Invented in 1974 (The University of British Columbia) • Ohio State University • Florida State University (Center for Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory) FOURIER TRANSFORM ION CYCLOTRON RESONANCE MASS SPECTROMETRY: A PRIMER Alan G. Marshall, Christopher L. Hendrickson, and George S. Jackson (1998) Mass Spectrometry Reviews 17, 1-35
Pacific Northwest National Laboratory - (Dr. Richard Smith) • University of Illinois (Dr. Neil Kelleher - Northwestern University) • Commercial instruments in many other institutes and universities
Condensed Theory of FT-MS F is the Lorentz Force observed by the ion when entering the magnetic field B is the magnetic field strength (constant) v is the incident velocity of the ion wc is the induced cyclotron frequency m is the mass of the ion z is the charge on the ion • Ions generated at the ionization source are introduced into the mass spectrometer by the use of high vacuum pump systems • By the time ions enter the ion trap (cell) : vacuum 10 -11 mBar, temperature absolute zero • The cell is located inside a spatially uniform superconducting magnetic field of usually between 4 – 15 Tesla cooled by liquid Helium and liquid Nitrogen • Ions are bent into a perpendicular circular path by the magnetic field • RF applied to ions • Ions with the same frequency with the RF are recorded, their intensity is proportional to the concentration of a particular ion
Diagramatic Scheme of ions in a FT MS – (Taken from U of Bristol, UK)