Infrared Irradiation in the Collision Cell of a Hybrid Tandem Quadrupole/Time-of-Flight Mass Spectrometer for Declustering and Cleaning of Nanoelectrosprayed Protein Complex Ions

摘要

Herein we report the performance of a hybrid quadrupolentime-of-flight tandem mass spectrometer with an improvedndesigned for coaxial infrared laser introduction for thencharacterization and dissociation of large protein complexnions and their aggregates formed under nanoelectrospraynionization. The major improvement from the originalndesign (Raspopov, S. A.; El-Faramawy, A.; Thomson,nB. A.; Siu, K. W. M. Anal. Chem. 2006, 78, 4572-4577)ninvolves the use of a hollow silica waveguide and physicalnisolation of the infrared laser. Large model protein complexnions and their aggregates examined include alcoholndehydrogenase, avidin, GroEL, and others. Gentle heatingnof these complexes with the infrared laser facilitatedndeclustering and resulted in better resolved mass spectralnpeaks and more accurate molecular-weight measurements.