title: MoS2-based nanoprobes for detection of silver ions in aqueous solutions and bacteria.
abstract: Silver as an extensively used antibacterial agent also poses potential threats to the environment and human health. Hence, in this work, we design a fluorescent nanoprobe by using rhodamine B isothiocyanate (RhoBS) adsorbed MoS2 nanosheets to realize sensitive and selective detection of Ag(+). On the surface of RhoBS-loaded MoS2 nanosheets, Ag(+) can be reduced to Ag nanoparticles, which afterward could not only lead to the detachment of RhoBS molecules and thus their recovered fluorescence but also the surface-enhanced fluorescence from RhoBS remaining adsorbed on MoS2. Such an interesting mechanism allows highly sensitive detection of Ag(+) (down to 10 nM) with great selectivity among other metal ions. Moreover, we further demonstrate that our MoS2-RhoBS complex could act as a nontoxic nanoprobe to detect Ag(+) in live bacteria samples. Our work resulted from an unexpected finding and suggests the promise of two-dimensional transition-metal sulfide nanosheets as a novel platform for chemical and biological sensing.
authors.affiliation: †State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Avenida da Universidade, Taipa, Macau, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Yang
authors.forename: Teng
authors.initials: T
authors.lastname: Liu
authors.forename: Liang
authors.initials: L
authors.lastname: Cheng
authors.forename: Guosheng
authors.initials: G
authors.lastname: Song
authors.forename: Zhuang
authors.initials: Z
authors.lastname: Liu
authors.affiliation: †State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Avenida da Universidade, Taipa, Macau, China.
authors.forename: Meiwan
authors.initials: M
authors.lastname: Chen
mesh_terms: D004220:Disulfides / Q000737:chemistry*; D004784:Environmental Monitoring / Q000379:methods; D004926:Escherichia coli / Q000737:chemistry*; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D007477:Ions / Q000032:analysis; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D015336:Molecular Probe Techniques; D015335:Molecular Probes / Q000737:chemistry; D008982:Molybdenum / Q000737:chemistry*; D012834:Silver / Q000032:analysis*; D012996:Solutions; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry
chemical_list: D004220:Disulfides; D007477:Ions; D015335:Molecular Probes; D012996:Solutions; D014874:Water Pollutants, Chemical; D014867:Water; D012834:Silver; D008982:Molybdenum; C082964:molybdenum disulfide
keywords: MoS2 nanosheets; bacteria; detection; selectivity; sensitivity