Highly selective colorimetric detection and estimation of Hg2+ at nano-molar concentration by silver nanoparticles in the presence of glutathione

Spectrochim Acta A Mol Biomol Spectrosc. 2015 Feb 25:137:503-8. doi: 10.1016/j.saa.2014.09.004. Epub 2014 Sep 8.

Abstract

The present study investigated the colorimetric detection of mercury (Hg(2+)) ions by using silver nanoparticles (Ag NPs) in the presence of glutathione. The nanoparticles used in the study were synthesized biologically by using Polyalthia longifolia leaf extract. The synthesized nanoparticles were characterized by UV-visible spectrophotometer, transmission electron microscope, X-ray diffraction, particle size analyzer and zeta sizer. The particles were spherical in shape and it possesses the effective diameter of 5 nm. The zeta potential of the particles was determined to be -28.6 mV. Ag NPs-glutathione conjugates were able to detect Hg(2+) in nanomolar level. Ag NPs-glutathione conjugates upon interaction with Hg(2+) changes from yellowish brown to pale yellow and finally colorless. The study may be applied for the qualitative and quantitative estimation of mercury at very low concentration.

Keywords: Biosynthesis; Colorimetric detection; Glutathione; Mercury; Silver nanoparticles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Colorimetry / methods*
  • Glutathione / chemistry*
  • Green Chemistry Technology
  • Mercury / analysis*
  • Metal Nanoparticles / chemistry*
  • Microscopy, Electron, Transmission
  • Plant Extracts / chemistry
  • Plant Leaves / chemistry
  • Polyalthia / chemistry
  • Sensitivity and Specificity
  • Silver
  • Spectrophotometry, Ultraviolet
  • Spectroscopy, Fourier Transform Infrared
  • X-Ray Diffraction

Substances

  • Plant Extracts
  • Silver
  • Mercury
  • Glutathione