Sensitive and selective detection of trivalent chromium using hyper Rayleigh scattering with 5,5′-dithio-bis-(2-nitrobenzoic acid)-modified gold nanoparticles

SENSORS AND ACTUATORS B-CHEMICAL

卷:178

Article

Hughes, Shantelle I.¹  Dasary, Samuel S. R.¹  Singh, Anant K.¹  Glenn, Zachery¹  Jamison, Hakim¹  Ray, Paresh C.¹  Yu, Hongtao¹ 

[1] Jackson State Univ, Dept Chem & Biochem, Jackson, MS 39217 USA

关键词: Gold nanoparticles;    Trivalent chromium;    5,5'-Dithio-bis-(2-nitrobenzoic acid);    Hyper rayleigh scattering;    pH dependence;    Colorimetric;   

DOI  :  10.1016/j.snb.2012.12.003

来源: Elsevier

【 摘 要 】

Hyper Rayleigh Scattering (HRS) and absorption spectral assays using surface-modified gold nanoparticles (AuNP) have been developed for sensitive and selective detection of trivalent chromium (Cr3+) from other metal ions including hexavalent chromium (as Cr2O72-). Gold nanoparticles of 13 nm, covalently attached with 5,5'-dithio-bis-(2-nitrobenzoic acid) (AuNP-DTNBA), is used as a probe for both the absorption and HRS assays. AuNP-DTNBA is able to detect Cr3+ at 25 ppb level at pH 6.0 using absorption spectral change of the AuNP-DTNBA. Visible color change can be observed when mixed with 250 ppb of Cr3+, while there is no color change when mixed with 2 ppm level of some of the most common metal ions such as Cr2O72-, Hg2+, Ba2+, Fe3+, Pb2+, Na+, Zn2+, Cd2+, Co2+, Mn2+, Ca2+, and Ni2+. However, a color change is observed when mixed with Ni2+, Zn2+, and Cd2+ at a concentration higher than 2 ppm. The detection limit for the HRS assay is on a remarkable 25 ppt level, and there is no detectable HRS signal at 2 ppm level for Cr2O72-, Hg2+, Ba2+, Fe3+, Pb2+, Na+, Zn2+, Cd2+, Co2+, Mn2+, Ca2+, and Ni2+. (c) 2013 Elsevier B.V. All rights reserved.

【 授权许可】

Free