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Label-free SERS study of galvanic replacement reaction on silver nanorod surface and its application to detect trace mercury ion.

ABSTRACT: It is significant to explore a rapid and highly sensitive galvanic replacement reaction (GRR) surface enhanced Raman scattering (SERS) method for detection of trace mercury ions. This article was reported a new GRR SERS analytical platform for detecting Hg(II) with label-free molecular probe Victoria blue B (VBB). In HAc-NaCl-silver nanorod (AgNR) substrate, the molecular probe VBB exhibited a strong SERS peak at 1609 cm(-1). Upon addition of Hg(II), the GRR occurred between the AgNR and Hg(II), and formed a weak SERS activity of Hg2Cl2 that deposited on the AgNR surfaces to decrease the SERS intensity at I1609 cm(-1). The decreased SERS intensity was linear to Hg(II) concentration in the range of 1.25-125 nmol/L, with a detection limit of 0.2 nmol/L. The GRR was studied by SERS, transmission electron microscopy and other techniques, and the GRR mechanism was discussed.

SUBMITTER: Wang Y

PROVIDER: S-EPMC4726172 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Label-free SERS study of galvanic replacement reaction on silver nanorod surface and its application to detect trace mercury ion.

Wang Yaohui Y Wen Guiqing G Ye Lingling L Liang Aihui A Jiang Zhiliang Z

Scientific reports 20160121

It is significant to explore a rapid and highly sensitive galvanic replacement reaction (GRR) surface enhanced Raman scattering (SERS) method for detection of trace mercury ions. This article was reported a new GRR SERS analytical platform for detecting Hg(II) with label-free molecular probe Victoria blue B (VBB). In HAc-NaCl-silver nanorod (AgNR) substrate, the molecular probe VBB exhibited a strong SERS peak at 1609 cm(-1). Upon addition of Hg(II), the GRR occurred between the AgNR and Hg(II), ...[more]

PMID: 26792071

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