Department of Chemistry Seminar Announcement

1. Department of Chemistry Seminar Announcement About the Speaker Prof Sunney X. Xie is a Mallinckrodt Professor of Chemistry and Chemical Biology at Harvard University. He received his BSc in chemistry from Peking University in 1984 and PhD in chemistry from University of California – San Diego under the direction of Professor John D Simon. He pursued his postdoctoral research with Professor Graham R Fleming at University of Chicago from 1990 – 1992. His research interests include single molecule spectroscopy, single molecule enzymology, molecular interactions, conformational dynamics, and underlying mechanishms of macromolecule machines, gene expression in living cells and nonlinear optical imaging and biomedical applications. Prof Sunney Xie was awarded the Berthold Leibinger Zukunftspreis for Laser Technology in 2008 and E.O. Lawrence Award in Chemistry in 2009. He is currently an Honorary Fellow of the Chinese Chemical Society and a member of National Academy of Science, USA. Abstract We recently developed a 3D multiphoton imaging technique, stimulated Raman scattering (SRS) microscopy, which allows imaging based on vibrational spectroscopy without the need for staining or fluorescent labeling. Chemical specificity of the technique is achieved by probing intrinsic vibrational properties of the molecules. Superb detection sensitivity is achieved by implementation of a high-frequency detection scheme and surpasses that of other label-free imaging techniques, such as spontaneous Raman scattering and coherent anti-Stokes Raman scattering (CARS) microscopy. Compared to CARS, SRS has the advantage that it does not suffer from an unwanted nonresonant background signal that distorts vibrational spectra and is linear in analyte concentration. We demonstrate video-rate SRS imaging in live anesthetized mice and present applications in drug delivery, lipid metabolism and medical diagnostics of brain pathologies. All are Welcome