Gas-phase separation using a trapped ion mobility spectrometer.

In the present work we describe the principles of operation, versatility and applicability of a trapped ion mobility spectrometer (TIMS) analyzer for fast, gas-phase separation of molecular ions based on their size-to-charge ratio. Mobility-based separation using a TIMS device is shown for a series for isobar pairs. In a TIMS device, mobility resolution depends on the bath gas velocity and analysis scan speed, with the particularity that the mobility separation can be easily tuned from low to high resolution (>50) in accordance with the analytical challenge. In contrast to traditional drift tube IMS analyzer, a TIMS device can be easily integrated in a mass spectrometer without a noticeable loss in ion transmission or sensitivity, thus providing a powerful separation platform prior to mass analysis.