Electrospray ionization Fourier transform ion cyclotron resonance at 9.4 T

Rapid Commun Mass Spectrom. 1996;10(14):1824-8. doi: 10.1002/(SICI)1097-0231(199611)10:14<1824::AID-RCM695>3.0.CO;2-E.


We present the first results from a new electrospray ionization Fourier transform ion cyclotron resonance mass spectrometer operated at a magnetic field of 9.4 T (i.e. > or = 2.4 T higher than for any prior FTICR instrument). The 9.4 T instrument provides substantially improved performance for large molecules (> or = 50% increase in mass resolving power) and complex mixtures (> or = 100% increase in dynamic range) compared to lower-field (< or = 6 T) instruments. The higher magnetic field makes possible larger trapped-ion population without introduction of significant space--charge effects such as spectral peak shift and/or distortion, and coalescence of closely-spaced resonances. For bovine ubiquitin (8.6 kDa) we observe accurate relative isotopic abundances at a signal-to-noise ratio greater than 1000:1, whereas a complete nozzle-skimmer dissociation electrospray ionization (ESI) FTICR mass spectrum of bovine carbonic anhydrase (29 kDa) is achieved from a single scan with a signal-to-noise ratio of more than 250:1. Finally, we are able to obtain mass resolving power, m/delta m > 200,000, routinely for porcine serum albumin (67 kDa). The present performance guides further modifications of the instrument, which should lead to significant further improvements.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Carbonic Anhydrases / chemistry
  • Cattle
  • Chromatography, High Pressure Liquid
  • Cyclotrons*
  • Electromagnetic Fields
  • Fourier Analysis
  • Mass Spectrometry / instrumentation*
  • Serum Albumin / chemistry
  • Ubiquitins / chemistry


  • Serum Albumin
  • Ubiquitins
  • Carbonic Anhydrases