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Updated: Aug 22, 2026

Time-resolved ElectroSpray Ionization Hydrogen-deuterium Exchange Mass Spectrometry for Studying Protein Structure and Dynamics
Published on: April 17, 2017
Evaluation of deuterium isotope effects in normal-phase LC-MS-MS separations using a molecular modeling approach
Sunil S Iyer1, Zong-Ping Zhang, Glen E Kellogg
1Department of Pharmaceutics, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298-0533, USA.
Abstract:
Molecular modeling of stationary phases presents a unique challenge because there is little available experimentally derived structural information. Verified interaction mechanisms at a molecular level with analytes are also rare. Molecular mechanics calculations using the Tripos force field were carried out to qualitatively and quantitatively assess stationary phase interactions. Binding energy values of -15.40, 15.28, -12.53, and -12.34 kcal/mol, respectively, are obtained for olanzapine (OLZ), OLZ-D3, des-methyl olanzapine (DES), and DES-D8 that corresponded to the retention behavior of the four compounds observed using liquid chromatography-mass spectrometry (MS)-MS. The model explains, semiquantitatively, the deuterium isotope effect in the normal-phase chromatographic separation of these compounds.
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