Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7641993 | Microchemical Journal | 2016 | 26 Pages |
Abstract
A novel, simple and highly sensitive plasmonic colorimetric method is developed for the detection of Pb2Â + in aqueous samples. The method is based on the aggregation of gold nanoparticles (AuNPs) or SiO2core-Aushell nanocomposites (SiO2@Au NCs) in the presence of Pb2Â + ions. It was found that the colour of AuNPs or SiO2@Au NCs changes in the presence of Pb2Â + ions and the intensity of surface plasmon resonance (SPR) peak of AuNPs or SiO2@Au NCs decreased. Thus, the synthesis of sensitive surface enhanced Raman scattering (SERS) materials; ~Â 20Â nm spherical AuNPs and ~Â 360Â nm SiO2@Au NCs leads to the development of nanosensor for the detection of Pb2Â + ions. Both AuNPs and SiO2@Au NCs by virtue of their versatility show localized surface plasmon resonance (LSPR) peaks at 522Â nm and 541Â nm respectively. The synthesized AuNPs, SiO2@Au NCs and analyte samples prepared were characterised using a scanning electron microscope, a transmission electron microscope and a UV-vis spectrophotometer. The SERS study was also used to compare sensitivities of both AuNPs and SiO2@Au NCs towards Pb2Â + ions using crystal violet (CV) as a target molecule. The analyte Pb2Â + was detected as low as 500Â nM using 20Â nm AuNPs and 50Â nM using 360Â nm SiO2@Au NCs. It was confirmed that SiO2@Au NCs were found ten times more sensitive as compared to AuNPs for the detection of Pb2Â + ions.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Sheenam Thatai, Parul Khurana, Surendra Prasad, Sarvesh K. Soni, Dinesh Kumar,