Lead (II) ion detection in surface water with pM sensitivity using aza-crown-ether-modified silver nanoparticles via dynamic light scattering

Nanotechnology. 2011 Jul 8;22(27):275504. doi: 10.1088/0957-4484/22/27/275504. Epub 2011 May 20.

Abstract

In this paper, we reported ultrasensitive lead ion detection in environmental water with pM sensitivity using aza-crown-ether-modified silver nanoparticles (ACE-Ag NPs) through dynamic light scattering (DLS). The colorimetric method based on ACE-Ag NPs is not capable of detecting Pb2+ ions over other metal ions (Fe3+, Co2+, Cu2+, Hg2+, Cd2+, Ag+, Li+, Na+, K+ and Cs+) with high sensitivity. But DLS has improved the selectivity and sensitivity of the Pb2+ detection system (50-fold or more) over colorimetric method, and its detection limit is 0.25 pM (1.03 ppt). The Pb2+ DLS assay can be applied to detect Pb2+ in the environmental water, such as in Yangtze and East Lake water samples with a detection limit of 0.20 and 0.22 pM, which is much lower than the maximum contamination level of 4.8×10(-8) M for lead in surface water defined by the national environmental quality standards of China (GB 3838-2002). Also, this method has a good performance in the determination of Pb2+ in drinking water, which is much lower than the maximum contamination level (MCL) of 72 nM for lead as defined by the US Environmental Protection Agency (EPA).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Colorimetry
  • Crown Ethers / chemical synthesis
  • Crown Ethers / chemistry*
  • Environment
  • Ions
  • Lead / analysis*
  • Light*
  • Metal Nanoparticles / chemistry*
  • Metal Nanoparticles / ultrastructure
  • Particle Size
  • Scattering, Radiation*
  • Silver / chemistry
  • Spectrophotometry, Ultraviolet
  • Spectroscopy, Fourier Transform Infrared
  • Surface Properties
  • Water / chemistry*

Substances

  • Crown Ethers
  • Ions
  • Water
  • Lead
  • Silver