The structure of gas-phase bradykinin fragment 1-5 (RPPGF) ions: an ion mobility spectrometry and H/D exchange ion-molecule reaction chemistry study.

Ion mobility-mass spectrometry (IM-MS) data is interpreted as evidence that gas-phase bradykinin fragment 1-5 (BK1-5, RPPGF) [M + H](+) ions exist as three distinct structural forms, and the relative abundances of the structural forms depend on the solvent used to prepare the matrix-assisted laser desorption ionization (MALDI) samples. Samples prepared from organic rich solvents (90% methanol/10% water) yield ions having an ion mobility arrival-time distribution (ATD) that is dominated by a single peak; conversely, samples prepared using mostly aqueous solvents (10% methanol/90% water) yield an ATD composed of three distinct peaks. The BK1-5 [M + H](+) ions were also studied by gas-phase hydrogen/deuterium (H/D) exchange ion-molecule reactions and this data supports our interpretation of the IM-MS data.

A fundamental introduction to ion mobility mass spectrometry applied to the analysis of biomolecules.

Chemists are constantly striving for techniques that add dimensions of orthogonality with increased throughput and sample complexity. Ion mobility spectrometry (IM) is a gas-phase separation method that adds new dimensions to mass spectrometry (MS). IM separates gas-phase ions based on their collision cross-section and can be coupled with time-of-flight (TOF) mass spectrometry to yield a powerful tool used in the identification and characterization of proteins and peptides.