ADVANTAGES OF HIGH MAGNETIC-FIELD FOR FOURIER-TRANSFORM ION-CYCLOTRONRESONANCE MASS-SPECTROMETRY

It is well-known that mass resolving power in Fourier transform ion cy clotron resonance mass spectrometry (FTICR MS) can increase linearly w ith increasing applied magnetic field induction, B, Here, we show that eight other FTICR primary performance parameters theoretically also i ncrease linearly (quadrupolar axialization efficiency, data acquisitio n speed), quadratically (upper mass limit, maximum ion kinetic energy, maximum number of trapped ions, maximum ion trapping duration, two-di mensional FTICR mass resolving power), or inverse-quadratically (peak coalescence tendency) with increasing B, The origin of (and conditions for) the magnetic field dependence of each of these parameters are pr esented and discussed, These fundamental advantages lead to corollary improvement in other FTICR performance parameters: e.g. signal-to-nois e ratio, dynamic range, mass accuracy, ion remeasurement efficiency an d mass selectivity for MS/MS, Finally, we note that these various adva ntages may be exploited in combination, so as to produce even higher e nhancement in a particular parameter: e.g. signal-to-noise ratio can i mprove by more than a factor of B-2 if mass resolving power is fixed a t the same value as at lower magnetic field.