Related Experiment Video
Updated: May 24, 2026

Mass Spectrometric Approaches to Study Protein Structure and Interactions in Lyophilized Powders
Published on: April 14, 2015
Localized hydration in lyophilized myoglobin by hydrogen-deuterium exchange mass spectrometry. 1. Exchange mapping
Andreas M Sophocleous1, Jun Zhang, Elizabeth M Topp
1Department of Industrial and Physical Pharmacy, Purdue University, West Lafayette, Indiana 47901, USA.
Abstract:
The local effects of hydration on myoglobin (Mb) in solid matrices containing mannitol or sucrose (1:1 w/w, protein:additive) were mapped using hydrogen-deuterium exchange with mass spectrometric analysis (HDX-MS) at 5 °C and compared to solution controls. Solid powders were exposed to D₂O(g) at controlled activity (a(w)) followed by reconstitution and analysis of the intact protein and peptides produced by pepsin digestion. HDX varied with matrix type, a(w), and position along the protein backbone. HDX was less in sucrose matrices than in mannitol matrices at all a(w) while the difference in solution was negligible. Differences in HDX in the two matrices were detectable despite similarities in their bulk water content. The extent of exchange in solids is proposed as a measure of the hydration of exchangeable amide groups, as well as protein conformation and dynamics; pepsin digestion allows these effects to be mapped with peptide-level resolution.
Related Concept Videos
¹H NMR of Labile Protons: Deuterium (²H) Substitution
Mass Spectrometry: Complex Analysis
GC–MS is a powerful hyphenated method commonly used in forensics and environmental...
¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
Hydrogen Bonds
Hydrogen Bonds Control the World!
Because hydrogen has very weak electronegativity when it binds with a strongly electronegative atom, such as oxygen or nitrogen, electrons in the bond are unequally shared.
High-Resolution Mass Spectrometry (HRMS)

