A colorimetric and surface-enhanced Raman scattering dual-signal sensor for Hg2+ based on Bismuthiol II-capped gold nanoparticles

• Published in: Analytica chimica acta Vol. 723; pp. 88 - 93
• Main Authors: Duan, Junling, Yang, Min, Lai, Yongchao, Yuan, Jingpeng, Zhan, Jinhua
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 20.04.2012; Elsevier
• Subjects: Analytical chemistry; Bismuthiol II; Chemistry; Colorimetry; Exact sciences and technology; Fresh Water - analysis; General, instrumentation; Gold; Gold - chemistry; Hydrogen-Ion Concentration; Ions - chemistry; Mercury; Mercury - analysis; Metal Nanoparticles - chemistry; Sensor; Spectrometric and optical methods; Spectrophotometry, Ultraviolet; Spectrum Analysis, Raman; Surface-enhanced Raman scattering; Thiadiazoles - chemistry; Gold; Colorimetry; Surface-enhanced Raman scattering; Bismuthiol II; Mercury; Sensor; Water; Gold II; Nanoparticle; Sample; Color; Metal ion; Concentration; Method; Chemical sensor; Aggregation; Sensitivity; Signal; Absorption; Detection limit; Surface Enhanced Raman Spectrometry; Detection; Ultraviolet visible spectrometry
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2012.02.031

A colorimetric and surface-enhanced Raman scattering (SERS) dual-signal sensor for Hg2+ with high sensitivity and selectivity has been developed based on Hg2+-induced anti-aggregation of Bismuthiol II–gold nanoparticles (AuNPs). [Display omitted] ► A dual-signal sensor for Hg2+ was developed by mixing Bismuthiol II and AuNPs. ► Colorimetric sensing was achieved based on the Hg2+-inhibited aggregation of AuNPs. ► Hot spots were formed with the aggregation of AuNPs, allowing SERS detection. ► The method showed high sensitivity and selectivity. The addition of Bismuthiol II to the gold nanoparticles (AuNPs) solution led to the aggregation of AuNPs with a color change from red to blue. As a result, hot spots were formed and strong surface-enhanced Raman scattering (SERS) signal of Bismuthiol II was observed. However, the Bismuthiol II-induced aggregation of AuNPs could be reversed by Hg2+ in the system, accompanied by a remarkable color change from blue to red. As evidenced by UV–vis and SERS spectroscopy, the variation in absorption band and SERS intensity was strongly dependent on the concentration of Hg2+, suggesting a colorimetric and SERS dual-signal sensor for Hg2+. The sensor had a high sensitivity, low detection limits of 2nM and 30nM could be achieved by UV–vis spectroscopy and by SERS spectroscopy, respectively. Other environmentally relevant metal ions did not interfere with the detection of Hg2+. The method was successfully applied to detect Hg2+ in water samples. It was simple, rapid and cost-effective without any modifying or labeling procedure.