MRI: Development of a Mass Spectrometer for Isomer-selective Thermochemical, Structural, and Spectroscopic Characterization for Bimolecular Interactions

This award is jointly supported by the Major Research Instrumentation, Chemical Measurement and Imaging, and the Chemistry Research Instrumentation Programs. The State University of New York at Stony Brook is developing an electrospray tandem mass spectrometer with variable temperature and ion trap capabilities for investigations of isomer-selective thermochemical, structural, and spectroscopic characterization of bimolecular interactions to support the research of Professor Christopher Johnson and colleagues Eszter Boros, Karena Chapman, and Michael White. This instrument facilitates research in the areas of biochemistry, medicinal chemistry, inorganic chemistry, organometallic catalysis, and physical chemistry. Tandem mass spectrometry facilitates the separation of ionized molecules as a function of space or time. The instrument being developed isolates analytes using mass spectrometry and generates weakly-bound or transient biomolecular complexes using variable temperature traps. Electron scattering and vibrational spectroscopy are directly integrated to determine structure and intermolecular interactions in samples. This instrument enhances the educational, research, and teaching efforts of students at all levels in many departments as well as provides accessibility for use at nearby institutions. The award for the development of a variable temperature ion trap mass spectrometer is aimed at enhancing research and education at all levels, especially in areas such as biochemistry, medicinal chemistry, inorganic chemistry, organometallic catalysis, and physical chemistry. Research focuses on the development of an instrument that generates isomer-specific thermochemical and structural analysis of bi- and polymolecular complexes. Instrument advances include operation in an environment ranging from cryogenic to elevated temperatures, conditions that are necessary for the generation or isolation of weakly-bound or transient bimolecular complexes and their thermochemical analysis. This platform facilitates the direct quantitative structural analysis of complexes via electron scattering measurements, and the vibrational spectroscopic analysis of structure and intermolecular interactions binding the complexes. The integration of these techniques into a single instrument platform enables the tracking of binding equilibria as a function of ion trap temperature to determine gas-phase binding enthalpies and entropies. In addition, electron scattering experiments and pair distribution function analysis will reveal the structures of these complexes by quantifying atom-atom distances in the bare analytes and their complexes. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.