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 1609 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.

Rhodamine 6G and Au�Pd core�shell nanorods: fluorescence enhancement for detection of mercury

“…(1), we obtain the detection limit 20.6 nM for our sensor B. Of course, the limit of detection of bimetallic nanoparticles with our fluorescence sensor based on the organic dye is somewhat higher than those typical for the sensors associated with monometallic nanoparticles and organic dyes, for which the loading content is close to 0.2-10.0 nM [18][19][20][21]. On the other hand, the mercury concentration level corresponding to our detection limit for the sensor B is less than the harmless level set by the Environmental Protection Agency for the tap water (Fact Sheet EPA-823-F-01-011, USA) [23].…”

“…Although our experimental data are not so amazing as those reported in Refs. [18][19][20][21], the detection limits in this study are lowered down to nM levels. In other words, we offer a ponderable alternative to the present-day techniques for instantaneous determination of Hg(II) contents, which is very simple and needs neither cumbersome sample preparation nor complicated instrumentation.…”

SERS spectral study of HAuCl4-cysteine nanocatalytic reaction and its application for detection of heparin sodium with label-free VB4r molecular probe

“…S5]. The SERS peaks appeared at 1184 cm −1 , 1197 cm −1 , 1386 cm −1 , 1477 cm −1 , 1617 cm −1 and so on, and the peak 1617 cm −1 was the strongest that ascribed to the bending vibration of C = N and C = C10. With the increase of the probe concentration, the SERS signal increased, and a linear relationship was obtained.…”

“…prepared the gold nanoparticles with caffeic acid as reducer, and the particle geometry could be controlled effectively by changing the caffeic acid concentration. Although silver nanoparticles commonly had higher SERS activity than gold nanoparticles, its stability was less than gold nanoparticles, and it was easier to be oxidized678910. Therefore, the preparation of gold nanoparticle with high SERS activity was very important to SERS quantitative analysis.…”

Recent Advances in Nanoparticle Shape and Composition Regulation Based on Galvanic Replacement for Cancer Treatment

“…Since the first report of Au nanocages synthesized from Ag nanocubes, various hollow Au nanoshell structures have been prepared using Ag nanospheres [144][145][146][147][148][149][150][151][152][153][154][155], Ag nanorods [156][157][158][159], Ag nanowires [160], and even Ag islands on two-dimensional surfaces as templates [161].…”