title: A colorimetric and surface-enhanced Raman scattering dual-signal sensor for Hg2+ based on Bismuthiol II-capped gold nanoparticles.
abstract: 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 Hg(2+) 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 Hg(2+), suggesting a colorimetric and SERS dual-signal sensor for Hg(2+). 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 Hg(2+). The method was successfully applied to detect Hg(2+) in water samples. It was simple, rapid and cost-effective without any modifying or labeling procedure.
authors.affiliation: Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, Department of Chemistry, Shandong University, Jinan 250100, China.
authors.forename: Junling
authors.initials: J
authors.lastname: Duan
authors.forename: Min
authors.initials: M
authors.lastname: Yang
authors.forename: Yongchao
authors.initials: Y
authors.lastname: Lai
authors.forename: Jingpeng
authors.initials: J
authors.lastname: Yuan
authors.forename: Jinhua
authors.initials: J
authors.lastname: Zhan
mesh_terms: D005618:Fresh Water / Q000032:analysis; D006046:Gold / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007477:Ions / Q000737:chemistry; D008628:Mercury / Q000032:analysis*; D053768:Metal Nanoparticles / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D013059:Spectrum Analysis, Raman; D013830:Thiadiazoles / Q000737:chemistry*
chemical_list: D007477:Ions; D013830:Thiadiazoles; C524587:bismuthiol II; D006046:Gold; D008628:Mercury