Colorimetric sensing of copper(II) based on catalytic etching of gold nanoparticles

Abstract

a b s t r a c tBased on the catalytic etching of gold nanoparticles (AuNPs), a label-free colorimetric probe was developed for the detection of Cu 2+ in aqueous solutions. AuNPs were first stabilized by hexadecyltrimethylammonium bromide in NH 3 -NH 4 Cl (0.6 M/0.

Highly Sensitive Visual Detection of Copper Ions Based on the Shape-Dependent LSPR Spectroscopy of Gold Nanorods

“…Two different linear relationships, one between the peak shift and Cu 2+ concentrations (1.0 to 20 nM, Figure 3C) and the other between the peak shift and logarithm of Cu 2+ concentrations (20 to 10 5 nM, Figure 3D), were respectively obtained. The detection limit was calculated to be 0.5 nM according to the S/N = 3 rule, which is lower than that of other nanoparticles and quantum-dot-based sensors, [7][8][9][10][11]17,18,28 and is comparable to the results obtained by AAS, AES, ICPMS, and anodic/cathodic stripping voltammetry (Table 1). 29−35 Digital photographs ( Figure 3E) show that the color of the GNR solutions changed from blue to red and even to colorless with increasing Cu 2+ content.…”

Ultrasensitive colorimetric detection of Cu2+ ion based on catalytic oxidation of l-cysteine

“…The electrochemistry methods show low detection limit and broad linear range, but possibly with the disadvantages of instability and interference of organics in anodic/catholic stripping voltammetry (Liu et al, 1999;Salaun and van den, Berg, 2006;Lin et al, 2012). The reported colorimetric methods can be realized by naked eyes but without ideal sensitivity (Lou et al, 2011;Liu et al, 2013;Shen et al, 2013;Wang et al, 2014). Our established method presented ideal sensitivity and simple operation processes.…”

“…Methods such as ICP-MS (Wu and Boyle, 1997;Dai et al, 2012) and AAS (Chan and Huang, 2000;Lima et al, 2012) can detect Cu 2 þ ion with high sensitivity and selectivity but with requirements of large instruments. Compared with electrochemical techniques (Liu et al, 1999;Salaun and van den Berg, 2006;Lin et al, 2012) and fluorescence methods (Chan et al, 2010;Yu et al, 2011;Yuan et al, 2013;Zhang et al, 2013) are much simpler with detection by naked eyes and UV-vis spectroscopy (Lou et al, 2011;Liu et al, 2013;Shen et al, 2013;Wang et al, 2014). However, till now, the reported colorimetric methods usually present higher detection limit and cannot easily accomplish real samples analysis.…”

A Highly Sensitive Colorimetric Method for Copper Ions Detection Based on Controlling the Peroxidase-like Activity of Au@Pt Nanocatalysts

“…Meanwhile, the color change could be easily observed just when the concentration of Cu 2+ was 20 nM. Compared with most of other colorimetric methods, our work was more sensitive 3,15,16,36,[40][41][42][43][44][45][46][47] (Table S2) , respectively. Then, mixtures were incubated with Au@Pt-NCs and applied to the color development reaction.…”