Journal
ANALYST
Volume 136, Issue 8, Pages 1690-1696Publisher
ROYAL SOC CHEMISTRY
DOI: 10.1039/c0an00903b
Keywords
-
Categories
Funding
- Institute of Bioengineering and Nanotechnology (Biomedical Research Council, Agency for Science, Technology and Research, Singapore)
Ask authors/readers for more resources
A simple colorimetric assay with high sensitivity, excellent selectivity and a tunable dynamic range is reported for detecting trace amounts of mercuric ion in aqueous solution based on the coordination of Hg2+ to the gold nanoparticle (AuNP)-associated 3-nitro-1H-1,2,4-triazole (NTA). The NTA can stabilize the AuNPs against tris-induced aggregation through capping the AuNPs. In the presence of Hg2+, the NTA is released from the AuNP surface via the formation of a NTA-Hg2+ coordination complex, leading to the aggregation of AuNPs in tris. This detection strategy is unique in terms of high sensitivity and excellent selectivity, a tunable dynamic range, and simplicity of probe preparation. Low detection limits of 7 nM (1.4 ppb) and 50 nM (10 ppb) can be achieved by spectrophotometer and by direct visualization, respectively, under the optimized conditions. No noticeable colour changes are observed towards other metal ions (Ag+, Zn2+, Ni2+, Cr3+, Mg2+, Cu2+, Co2+, Cd2+, Pb2+, Fe2+) at concentrations up to 100 mu M without the need of any other masking agents. In addition, the dynamic range of the assay can be easily tuned by adjusting the amount of NTA in the NTA-AuNP probes. More importantly, the NTA-AuNP probes can be simply prepared by mixing NTA with as-synthesized citrate-capped AuNPs. This not only avoids complicated surface modifications and tedious separation processes, but also is cost-effective.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available