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

Herein we report the performance of a hybrid quadrupole time-of-flight tandem mass spectrometer with an improved designed for coaxial infrared laser introduction for the characterization and dissociation of large protein complex ions and their aggregates formed under nanoelectrospray ionization The major improvement from the original design (Raspopov, S A, El-Faramawy, A, Thomson, B A, Siu, K. W M Anal Chem 2006, 78, 4572-4577) involves the use of a hollow silica waveguide and physical isolation of the infrared laser Large modE 1 protein complex ions and their aggregates examined include alcohol dehydrogenase, avidin, GroEL, and others Gentle heating of these complexes with the Infrared laser facilitated declustering and resulted in better resolved mass spectral peaks and more accurate molecular-weight measurements