In matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS), a pulsed laser ionizes molecules from a sample for mass spectral characterization. In Dr. Yeung’s laboratory, this technique is applied to map the spatial distributions of important molecules in brain tissue for neuroscience research.  That is, mass spectra are collected continuously while the tissue sample is moved orderly in two dimensions. Plotting the intensities of a selected mass over the scanned areas allows us to generates MS images of the tissue shown above.

Importantly, MS imaging is advantageous over other imaging technique because it does not require prior labeling of the analyte of interest and thus can be used in a non-targeted approach to identify changes of a variety of molecules with clinical relevance.

Students in the Yeung Lab work in collaboration with researchers in the Schulich School of Medicine & Dentistry and apply MALDI MS imaging to determine the spatial distributions of various molecules including peptides, lipids and neurotransmitters.  Generally, they are interested in studying how changes of these molecules in specific brain regions are functionally related to signaling and/or mental health-related symptoms.

Additional to tissue imaging research, Dr. Yeung also collaborates with Dr. Mark Sumarah at Agriculture and Agri-Foods Canada in identifying mycotoxins and environmental pollutants relevant to the Canadian agriculture, using liquid chromatography electrospray ionization mass spectrometry (LC ESI MS) as the primary analytical tool. 

Another ongoing collaboration is with Dr. Franco Berruti (Department of Chemical and Biochemical Engineering). Their collaborative research takes place at the Institute for Chemicals and Fuels from Alternative Resources (ICFAR) which focuses in biomass and waste conversion for alternative fuels and/or specialty chemicals.

To obtain additional information on Dr. Yeung’s work, please refer to the publications listed.

If you are interested in joining the Yeung research group for graduate studies, please visit the Department of Chemistry website for admission information.