SIMPLE METHOD FOR ION ISOLATION IN FOURIER-TRANSFORM ION-CYCLOTRON RESONANCE MASS-SPECTROMETRY - COMBINED NOTCH EXCITATION AND SELECTIVE ION PARTITIONING IN A DUAL CELL

A simple approach is described for the mass selection of ions in Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry. The method is based on the principles of notch ejection and selective ion partitioning in a dual cell. In most instances, the application of only two radiofrequency pulses allows the isolation of the desired ion from a mixture of ions with mass values over a wide range. This is also true in cases for which several interfering ions have similar mass values to the ion to be isolated. This method is readily applied in most custom-built and commercial dual-cell FT-ICR devices without modification of the hardware or software.