electrospray ion mobility mass spectrometer is used for a variety of projects
including structural studies and investigations of biomolecule hydration.
A schematic of the experimental setup is shown below. Ions are formed
by electrospray ionization and transferred into the vacuum system via
a capillary followed by an ion funnel, which is also used as an ion-storage
and pulsing device. Ions are then injected into a drift cell and are pulled
through by a weak electric field. In mobility
experiments, the cell is filled with several Torr of helium. In temperature-dependent
equilibrium experiments, the cell contains a neutral reactant gas.
Ions exiting the cell are mass analyzed in a quadrupole mass spectrometer,
and finally detected. A more detailed description of the instrumentation
can be found on this site here and published
in the literature [Wyttenbach,
T.; Kemper, P. R.; Bowers, M. T. Int. J. Mass Spectrom. 2001,