Where the resolving power of IM-MS techniques is insufficient to differentiate challenging isomers, various chemical approaches have been used to alter their mobility with the goal of better separations. We are primarily focused on simple, fast, and inexpensive reactions targeting common steroid functional groups. Thus far, we have published on reactions with ozone, simple carbonyls like acetone (i.e., Paterno-Buchi reaction), and derivatizations with Girard’s reagents and carbonyl diimidazole. Our group has also looked at simple, noncovalent complexation with compounds like cyclodextrins.

Representative Papers:

1. Improved analysis of derivatized steroid hormone isomers using ion mobility-mass spectrometry (IM-MS)
2. Improved Ion Mobility Separation and Structural Characterization of Steroids using Derivatization Methods
3. Improved Identification of Isomeric Steroids Using the Paternò-Büchi Reaction with Ion Mobility-Mass Spectrometry
4. Ozone-Induced Cleavage of Endocyclic C═C Double Bonds within Steroid Epimers Produces Unique Gas-Phase Conformations