Full, Associate, or Assistant ProfessorIndiana University Indianapolis School of ScienceThe School of Science (SoS) at Indiana University Indianapolis (IU Indianapolis) and newly established IU Conver...

YouTube video by Michael T Marty

Cerebrosides, a class of biologically important lipids, are comprised of a monosaccharide head group along with their ceramide tail. However, their ac…

Cross-linking and covalent labeling are common tools for protein structural elucidation by mass spectrometry. However, despite the importance of electrostatic interactions in proteins, there are not m...

Per- and polyfluoroalkyl substances (PFAS) are synthetic organofluorine compounds that accumulate in the environment due to significant industrial use and resistance to degradation. PFAS are of global interest because of their environmental and health concerns. They exist in a variety of linear and nonlinear forms containing a variety of isomers, as well as differing functional headgroups for each class. That structural complexity requires advanced analytical techniques, beyond current high-resolution mass spectrometry (HRMS) methods, for their accurate identification and quantification in a wide range of samples. Herein, we demonstrate the power of Structures for Lossless Ion Manipulations (SLIM)-based high-resolution ion mobility (HRIM) for separation of complex PFAS branched isomers. SLIM is integrated into a multidimensional LC-SLIM IM-MS/MS workflow, developed for the extensive characterization of a wide range of PFAS compounds. As we surveyed sulfonate and carboxylic acid classes of PFAS, we observed unique arrival time vs m/z trend lines that were representative of each class; these trend lines are important for allowing identification of emerging species based on their placement in that two-dimensional space. Next, we used complementary tandem mass spectrometry (MS/MS) approaches with all ion fragmentation (AIF), as well as energy-resolved MS/MS, to further investigate the structure of mobility-separated species. This allowed both investigation of fragmentation mechanism and identification of unique fragment ions that could allow differentiation of isomers when ion mobility was insufficient. Overall, the combination of chromatography, high-resolution SLIM, and MS/MS provided a comprehensive workflow capable of identifying unknown emerging PFAS compounds in complex environmental samples.

Fentanyl has become a growing concern as a deadly drug of abuse. In this work, we use a novel ion mobility–mass spectrometry (IM-MS) approach with metal cation adducts and high-resolution demultiplex...

Native ion mobility-mass spectrometry combined with collision-induced unfolding (CIU) is a powerful analytical method for protein characterization, offering insights into structural stability and enab...

Recently, the use of mass distribution–based isotopic shifts in high-resolution ion mobility spectrometry-mass spectrometry–based separations have enabled isomer delineation by measuring the relative ...

Phosphorylation of serine 129 (pS129) in the intrinsically disordered protein alpha synuclein has long been associated with neurodegenerative disease. In the past several years, the functional relevan...

The benefits of native mass spectrometry have led to the extensive study of proteins inside mass spectrometers in the gas phase. The expansion of native mass spectrometry requires novel tools for gai...

Advancing Mass Spectrometry for Biophysics and Structural Biology