Julia Laskin

Title: Ambient Mass Spectrometry Imaging: Recent Developments and Opportunities

Department of Chemistry, Purdue University, West Lafayette, IN, United States

Abstract:

Mass spectrometry imaging (MSI) is a powerful technique for studying the localization of lipids, metabolites, and proteins in biological samples. We have developed nanospray desorption electrospray ionization (nano-DESI), an ambient ionization technique that enables label-free molecular imaging of biological samples with minimal sample pretreatment. Nano-DESI relies on the localized liquid extraction of analyte molecules from the sample into a liquid bridge formed between two glass capillaries. The extracted analytes are transferred to a mass spectrometer inlet and ionized by electrospray ionization. Quantification is performed by adding an internal standard to the solvent and normalizing the signals of endogenous analytes to the corresponding adduct of the standard. Recent developments of nano-DESI MSI instrumentation have enabled quantitative imaging of lipids, metabolites, and proteins in tissues with high sensitivity and spatial resolution down to 8-10 microns using finely pulled capillaries. Furthermore, we have developed a microfluidic nano-DESI probe, which greatly simplifies the experimental setup and demonstrates similar performance to the capillary-based probe. We have enhanced the chemical specificity of nano-DESI MSI experiments by coupling it with ion mobility spectrometry and online photochemical derivatization of the extracted analytes. These complementary approaches have been used for isomer-selective imaging of biomolecules in tissue samples. Collectively, these new spatial omics approaches provide unique insights into the biochemical pathways in biological systems.

Bio:

Julia Laskin, M.Sc. in Physics from the Leningrad Polytechnical Institute (1990); Ph.D. in Physical Chemistry from the Hebrew University of Jerusalem (1998); Postdoctoral fellow with Dr. Jean Futrell at the University of Delaware and Pacific Northwest National Laboratory (PNNL). Dr. Laskin is currently a William F. and Patty J. Miller Professor of Analytical Chemistry at Purdue University. Prior to joining Purdue, she was a scientist at PNNL (2002-2017) and was promoted to the highest scientific rank in 2011.

Dr. Laskin’s research is focused on understanding phenomena underlying collisions of complex ions with surfaces for selective modification of substrates using beams of mass-selected ions and development of new approaches for quantitative molecular imaging of biological samples using mass spectrometry. In her research, she has developed unique instrumentation to study soft landing of ions for highly selective surface modification for applications in energy storage, catalysis, and biology. Her work on the development of nanospray desorption electrospray ionization (nano-DESI) has enabled quantitative ambient imaging of fully hydrated biological samples in their native environment with subcellular resolution and analysis of complex mixtures directly from solid substrates. Her research has resulted in over 310 peer-reviewed publications including invited reviews and book chapters and 11 patents.

Dr. Laskin is Past President of the American Society for Mass Spectrometry (ASMS) and an editor-in-chief of the International Journal of Mass Spectrometry. She was Vice President for Programs and President of the ASMS, a co-organizer of the 2019 ASMS Asilomar Conference on Imaging Mass Spectrometry, and a chair of the 2017 Gordon Research Conference on Gaseous Ions.  Her research has been honored with several prestigious awards including Presidential Early Career Award (2007), ASMS Biemann Medal (2008), Honor issue of JASMS (2009), Inaugural Rising Star Award of the ACS Women Chemists Committee (2011), PNNL Director’s Science and Engineering Achievement Award (2014), Medal of the Russian Society for Mass Spectrometry (2017), the Ron Hites Award (2019), The Riveros Medal of the Brazilian Mass Spectrometry Society (2022), Advances in Measurement Science Lectureship Award (2023), and other. She is a member of the Editorial Board of Mass Spectrometry Reviews, Chemistry Methods, and Advanced Structural and Chemical Imaging.