A triaxial probe for on-line proteolysis coupled with hydrogen/deuterium exchange-electrospray mass spectrometry.

Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996-1600, USA.
Journal of the American Society for Mass Spectrometry (Impact Factor: 3.19). 03/2007; 18(2):208-17. DOI: 10.1016/j.jasms.2006.09.011
Source: PubMed

ABSTRACT An on-line proteolysis system utilizing a triaxial electrospray probe was developed to aid localization of the hydrogen-bonding interaction sites in hydrogen/deuterium exchange-mass spectrometry (HDX-MS) studies of Abeta (1-40) fibrils. The probe allows delayed introduction of the organic solvent component needed for stable electrospray, thus enhancing hydrolysis performance relative to that of a coaxial probe. Effective on-line digestion was accomplished in approximately 12 s. The probe should be of general utility for HDX-MS studies of amyloid fibrils and other protein aggregates.

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