Speaker: Dr. Steven Ray, University at Buffalo, Department of Chemistry 

Host: Dr. Alex Gundlach-Graham

New instrumental approaches and chemical measurement strategies are often required in order to address emerging, increasingly complex, chemical questions. When new chemical measurement capabilities are realized, they often find use within a much wider community of chemists. In this presentation, several new instrumental approaches being developed with this aim will be briefly presented.

A new type of mass analyzer known as the distance-of-flight mass spectrometer (DOFMS) will be described. The DOFMS concept is best explained by comparison with traditional time-of-flight mass spectrometry (TOFMS). The TOFMS strategy measures the mass-to-charge (m/z) of an ion by imparting the same energy to all ions and then measuring the time required for each m/z to traverse a distance and arrive at a single detector. In contrast, DOFMS measures the m/z of an ion by measuring the distance each ion travels during a set time period. Because of this unique ability to physically separate ions according to m/z, new capabilities for ion detection and collection have emerged. Specifically, the development of a new type of semiconductor ion detection array application-specific integrated chip will be discussed as an advantageous detector for this new approach to mass spectrometry.

Second, a new, simple instrumental approach for atomic emission spectrometry will be examined. The solution-cathode glow discharge (SCGD) is an atmospheric pressure glow discharge sustained in the ambient atmosphere that is anchored to a liquid surface. The glow discharge plasma is responsible for removing material from the liquid and exciting the constituent atoms to emission for quantitation be atomic emission spectrometry (AES). Despite its small size and simplicity, the SCGD has achieved limits of detection comparable to more conventional AES methods. The experimental setup and operating principles of the SCGD will be discussed, and its future for AES examined.

Finally, will consider several different applications of microwave energy in mass spectrometry applications. Specifically, MS-instruments often make use of convective heating interfaces to aid vaporization/desolvation in atmospheric-pressure ion sources, such as electrospray ionization (ESI). Recently, our laboratory has developed a method to study the effects of microwave heating and desolvation upon the formation of the gas phase ions by ESI process. Using this strategy, microwaves are focused into a small volume near the tip of an ESI emitter by means of a novel coaxial waveguide structure. When the microwave radiation is absorbed, it induces very rapid evaporation through dielectric heating, modifying the features of the Taylor cone and affecting processes such as droplet generation, jet stability, ionization intensity and efficiency, and ion fragmentation. The capabilities of this new microwave-assisted electrospray ionization source (µAESI) and the advantages it holds for mass spectrometry will be described.

Bio: Steven Ray, Ph.D. is currently the Winkler Assistant Professor of Chemistry in the Department of Chemistry, State University of New York at Buffalo. Steve received his B.S. in Chemistry from Hope College (Holland, MI), and Ph.D. from Indiana University under the direction of Professor Gary Hieftje. He worked as the Senior Mass Spectrometrist for Indiana University before becoming an Associate Research Scientist in the Laboratory for Spectrochemistry at IU. Steven moved to SUNY-Buffalo in 2015. Dr. Ray has published more than 90 manuscripts and book chapters, and holds 9 patents. He serves on the editorial advisory boards of the Journal of Analytical Atomic Spectrometry, Applied Spectroscopy, Spectrochimica Acta, Part B, Atomic Spectroscopy, and Spectroscopy magazine. Dr. Ray was the recipient of the 2016 Young Plasma Spectrochemist Award, the 2015 ‘Best Paper’ Award given by Analytical and Bioanalytical Chemistry, the 2014 Lester Strock Medal from the Society for Applied Spectroscopy, the 2013 Ron Hites Award given by the American Society for Mass Spectrometry for the best paper in the Journal of the American Society for Mass Spectrometry, and a 2011 R&D100 Award. He is a Fellow of the Royal Society of Chemistry. His research interests involve novel aspects of analytical instrumentation development and plasma spectrometry, including time-of-flight mass spectrometry, distance-of-flight mass spectrometry, liquid-based glow discharge emission spectrometry, and microwave-enabled measurement approaches.

Steven J. Ray - Department of Chemistry - University at Buffalo