讲座概要
Structure and dynamics of condensed-phase systems such as organic chromophores and biosensors govern their functions which broadly impact the chemical, biological, energy and health fields. However, a complete understanding of their working mechanisms is hindered by the lack of suitable tools that can resolve atomic motions on intrinsic molecular timescales. This talk discusses the table-top wavelength-tunable femtosecond stimulated Raman spectroscopy (FSRS), aided by transient absorption spectroscopy and quantum calculations/molecular dynamics simulations, which have captured molecular movies for fluorescence and other nonradiative events like never before. Representative examples include the green and yellow fluorescent protein (GFP/YFP) from jellyfish that can be engineered to emit from blue, green to red and sense calcium (Ca 2+) and chloride ions (Cl – ) in a ratiometric manner, revealing the ultrafast interplay between excited-state events such as proton transfer, cis-trans isomerization, dark state formation, and conformational trapping (i.e., rigidity). Similar chromophore ring-twisting motions found inside a metal-organic complex are implicated for photocatalysis with implications of herbicide removal in waterways. Such mechanistic understandings have propelled us to delineate the multidimensional excited-state potential energy surface and rationally design and engineer FP-based biosensors as well as other functional systems with strategic substitutions, improved functions, and societal benefits.
凝聚相体系的结构及动力学是实用功能体系的基石，在化学、生物、能源及健康领域内有深远影响。团队发展了波长可调的飞秒受激拉曼光谱（femtosecond stimulated Raman spectroscopy，FSRS）关键技术，与瞬态吸收电子光谱及量子化学计算/分子动力学模拟相辅相成，用以拍摄荧光发射和其它非辐射弛豫通道的分子电影。这种深入的对机制的领悟将准确描绘多维反应激发态势能面，并能合理设计发展具有关键突变以及更高性能的生物传感器及其它功能材料体系。
主讲人介绍
Dr. Chong Fang is the tenured Full Professor of Chemistry and Patricia Valian Reser Endowed Faculty Scholar in Science at Oregon State University, USA. Dr. Fang earned Ph.D. (2006) from the late Prof. Robin Hochstrasser at UPenn focusing on 2D-IR studies of biomolecules from helices to drug-enzyme complexes in aqueous solution (a PNAS Cover in 2007), and performed his postdoctoral research with Prof. Richard Mathies at UC Berkeley (2007–2010) on the wild-type GFP fluorescence mechanism (a Nature Cover in 2009). Earlier, Dr. Fang obtained dual B.S. in Chemical Physics and Applied Computer Science from USTC (1996–2001), where he received the Guo Moruo Scholarship in 2000. Since 2010, the Fang Group at Oregon State has developed state-of-the-art ultrafast spectroscopic toolsets including tunable femtosecond stimulated Raman spectroscopy (FSRS) and broadband up-converted multicolor array (BUMA) to capture “molecular movies” and elucidated the structure-function relationships of molecular systems ranging from biosensors and proteins (ACIE, PCCP, and CAJ Covers in 2023; ChemPhotoChem Cover in 2024), photoacids to metal-organic complexes (a JPCL Cover in 2018 and a Chem. Phys. Rev. Cover in 2024), and battery electrolytes (a Carbon Energy Cover in 2021 and a Nat. Sustain. Cover in 2023). His research has been featured in Imaging & Microscopy (Germany), The Analytical Scientist and Research Features (UK), ScienceDaily, Phys.org, Medical News Today, Modern Metals, and KMTR TV (USA), to name a few. Notable accolades include the NSF CAREER Award (2015–2021), the inaugural 2015 Robin Hochstrasser International Young Investigator Award (Elsevier and Chemical Physics), the 2016 OSU Promising Scholar Award and Milton Harris Faculty Teaching Award, the 2019 OSU Impact Award for Outstanding Scholarship, the 2021 College of Science Milton Harris Award in Basic Research, the 2023 OSU Excellence in Postdoctoral Mentoring Award and D. Curtis Mumford Faculty Service Award, and the 2024-2025 Visiting Professorship at Dalian Institute of Chemical Physics, Chinese Academy of Sciences.
方翀，美国俄勒冈州立大学化学系终身全职教授，Patricia Valian Reser科学讲席教授。中国科技大学化学物理和应用计算机科学本科双学位，获郭沫若奖学金，宾夕法尼亚大学博士，师从Robin Hochstrasser，加州伯克利大学博士后。在Nature、PNAS等发表多篇封面论文。开发了最先进的超快光谱工具集。获美国国家科学基金会早期职业生涯发展奖等多种荣誉。
( 图文/FANG CHONG、编辑/李璐瑶 刘怡宁、初审/蒙晨、复审/赖凯声、终审/汪勇)
