Increasing Collisional Activation of Protein Complexes Using Smaller Aperture Source Sampling Cones on a Synapt Q-IM-TOF Instrument with a Stepwave Source.

ABSTRACT: Quadrupole ion mobility time-of-flight (Q-IM-TOF) mass spectrometers have revolutionized investigation of native biomolecular complexes. High pressures in the sources of these instruments aid transmission of protein complexes through damping of kinetic energy by collisional cooling. As adducts are removed through collisional heating (declustering), excessive collisional cooling can prevent removal of nonspecific adducts from protein ions, leading to inaccurate mass measurements, broad mass spectral peaks, and obfuscation of ligand binding. We show that reducing the source pressure using smaller aperture source sampling cones (SC) in a Waters Synapt G2-Si instrument increases protein ion heating by decreasing collisional cooling, providing a simple way to enhance removal of adducted

SUBMITTER: Wilson JW 

PROVIDER: S-EPMC7855748 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature