Filtered white noise and repetitive chirp broadband quadrupolar excitation Fourier transform ion cyclotron resonance mass spectrometry at 1 tesla

Abstract

Radiofrequency (RF) chirp and filtered white noise are compared as waveforms for broadband quadrupolar excitation. Ions are formed by matrix-assisted laser desorption Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry and axialized by quadrupolar excitation. Both quadrupolar excitation waveforms are capable of axializing ions over a range of masses. Remeasurement efficiencies for repetitive chirp excitation are greater than 98%. Remeasurement efficiencies for noise excitation are lower, 80%. The duration of transients recorded using either broadband excitation method is several orders of magnitude longer than for ions that have not been axialized.