Gas Phase Hydration of Trapped Peptides: Kinetics

摘要

Gas phase proteins provide the opportunity to study hydrated biomolecules. Peptides/proteins have been hydrated by optimizing ESI parameters to preserve water on the biomolecule ions or by adding water to unsolvated biomolecules during transmission through a drift tube gas including water vapor. The present study hydrates peptides stored in an ion trap by exposing the ion cloud to a continuously flowing helium/water vapor mixture. Hydrated peptides and proteins were successfully observed for long exposures and elevated temperatures providing new opportunities to study hydrated gas phase biomolecules. This technique can achieve hydration levels and timescales required to observe the dependence of kinetics measurements on conformation, charge state and sequence composition. This method may be combined with other techniques including mobility and ion spectroscopy to provide a broad array of measurements on hydrated biomolecules in gas phase.