title: Alkyne-functionalized superstable graphitic silver nanoparticles for Raman imaging.
abstract: Noble metals, especially gold, have been widely used in plasmon resonance applications. Although silver has a larger optical cross section and lower cost than gold, it has attracted much less attention because of its easy corrosion, thereby degrading plasmonic signals and limiting its applications. To circumvent this problem, we report the facile synthesis of superstable AgCu@graphene (ACG) nanoparticles (NPs). The growth of several layers of graphene onto the surface of AgCu alloy NPs effectively protects the Ag surface from contamination, even in the presence of hydrogen peroxide, hydrogen sulfide, and nitric acid. The ACG NPs have been utilized to enhance the unique Raman signals from the graphitic shell, making ACG an ideal candidate for cell labeling, rapid Raman imaging, and SERS detection. ACG is further functionalized with alkyne-polyethylene glycol, which has strong Raman vibrations in the Raman-silent region of the cell, leading to more accurate colocalization inside cells. In sum, this work provides a simple approach to fabricate corrosion-resistant, water-soluble, and graphene-protected AgCu NPs having a strong surface plasmon resonance effect suitable for sensing and imaging.
authors.affiliation: Molecular Sciences and Biomedicine Laboratory, State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology and Collaborative Innovation Center for Molecular Engineering and Theronastics, Hunan University , Changsha 410082, China.
authors.forename: Zhi-Ling
authors.initials: ZL
authors.lastname: Song
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Chen
authors.forename: Xia
authors.initials: X
authors.lastname: Bian
authors.forename: Li-Yi
authors.initials: LY
authors.lastname: Zhou
authors.forename: Ding
authors.initials: D
authors.lastname: Ding
authors.forename: Hao
authors.initials: H
authors.lastname: Liang
authors.forename: Yu-Xiu
authors.initials: YX
authors.lastname: Zou
authors.forename: Shan-Shan
authors.initials: SS
authors.lastname: Wang
authors.forename: Long
authors.initials: L
authors.lastname: Chen
authors.forename: Chao
authors.initials: C
authors.lastname: Yang
authors.forename: Xiao-Bing
authors.initials: XB
authors.lastname: Zhang
authors.forename: Weihong
authors.initials: W
authors.lastname: Tan
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D003300:Copper / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D061986:MCF-7 Cells; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D013499:Surface Properties
chemical_list: D000480:Alkynes; D012834:Silver; D011092:Polyethylene Glycols; D006108:Graphite; D003300:Copper