title: SERS imaging of cell-surface biomolecules metabolically labeled with bioorthogonal Raman reporters.
abstract: Live imaging of biomolecules with high specificity and sensitivity as well as minimal perturbation is essential for studying cellular processes. Here, we report the development of a bioorthogonal surface-enhanced Raman scattering (SERS) imaging approach that exploits small Raman reporters for visualizing cell-surface biomolecules. The cells were cultured and imaged by SERS microscopy on arrays of Raman-enhancing nanoparticles coated on silicon wafers or glass slides. The Raman reporters including azides, alkynes, and carbondeuterium bonds are small in size and spectroscopically bioorthogonal (background-free). We demonstrated that various cell-surface biomolecules including proteins, glycans, and lipids were metabolically incorporated with the corresponding precursors bearing a Raman reporter and visualized by SERS microscopy. The coupling of SERS microscopy with bioorthogonal Raman reporters expands the capabilities of live-cell microscopy beyond the modalities of fluorescence and label-free imaging.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Synthetic and Functional Biomolecules Center, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871 (China).
authors.forename: Ming
authors.initials: M
authors.lastname: Xiao
authors.forename: Liang
authors.initials: L
authors.lastname: Lin
authors.forename: Zefan
authors.initials: Z
authors.lastname: Li
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.forename: Senlian
authors.initials: S
authors.lastname: Hong
authors.forename: Yaya
authors.initials: Y
authors.lastname: Li
authors.forename: Meiling
authors.initials: M
authors.lastname: Zheng
authors.forename: Xuanming
authors.initials: X
authors.lastname: Duan
authors.forename: Xing
authors.initials: X
authors.lastname: Chen
mesh_terms: D004926:Escherichia coli / Q000378:metabolism; D008563:Membrane Lipids / Q000737:chemistry / Q000378:metabolism*; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D008855:Microscopy, Electron, Scanning; D011134:Polysaccharides / Q000737:chemistry / Q000378:metabolism*; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D008563:Membrane Lipids; D008565:Membrane Proteins; D011134:Polysaccharides
keywords: Raman imaging; SERS imaging; biomolecules; bioorthogonality; cell surface