Enhancements in travelling wave ion mobility resolution

TLDR

Ion mobility separation provides collision cross‑section information, and traveling‑wave ion mobility in a quadrupole/time‑of‑flight mass spectrometer enables routine CXS measurements across diverse ions at physiologically relevant concentrations. The authors aim to discuss technical advances in the second‑generation traveling‑wave ion mobility separator. These advances produce up to a four‑fold increase in mobility resolution. The enhanced resolution is demonstrated with reverse peptides, small ruthenium‑containing anticancer drugs, a cisplatin‑modified protein, and the GroEL chaperone complex, and the measured collision cross‑sections agree with previous generation and theoretical values. © 2011 John Wiley & Sons, Ltd.

Abstract

The use of ion mobility separation to determine the collision cross‐section of a gas‐phase ion can provide valuable structural information. The introduction of travelling‐wave ion mobility within a quadrupole/time‐of‐flight mass spectrometer has afforded routine collision cross‐section measurements to be performed on a range of ionic species differing in gas‐phase size/structure and molecular weight at physiologically relevant concentrations. Herein we discuss the technical advances in the second‐generation travelling‐wave ion mobility separator, which result in up to a four‐fold increase in mobility resolution. This improvement is demonstrated using two reverse peptides (mw 490 Da), small ruthenium‐containing anticancer drugs (mw 427 Da), a cisplatin‐modified protein (mw 8776 Da) and the noncovalent tetradecameric chaperone complex GroEL (mw 802 kDa). What is also shown are that the collision cross‐sections determined using the second‐generation mobility separator correlate well with the previous generation and theoretically derived values. Copyright © 2011 John Wiley & Sons, Ltd.