Ultra-low level optical detection of mercuric ions using biogenic gold nanotriangles

Amit Singh, Renu Pasricha, Murali Sastry

Research output: Contribution to journalArticle

Abstract

Mercury is a serious environmental pollutant known to have detrimental health effects in all life forms. Here, we report the use of biologically synthesized aqueous gold nanotriangles for sensitive and selective optical detection of femto-molar levels of mercury ions by exploiting the high amalgamation tendency of mercury metal towards gold. Aqueous chloroaurate ions were reduced using lemongrass (Cymbopogon flexuosus) leaf extract at room temperature to form gold nanotriangles. Mercuric (Hg 2+) ions were reduced in the presence of these triangles to facilitate amalgamation and the optical properties were monitored. We observe a significant change in the longitudinal plasmon absorption band of the nanotriangles even at femto-molar concentrations of mercuric ions. High-resolution transmission electron microscopy confirms changes in particle morphology at such low concentrations. This protocol shows no sensitivity to other environmentally relevant metal ions, including Pb 2+, Zn 2+, Cd 2+, Fe 2+, Ni 2+, Sr 2+, Ca 2+, Mn 2+, and Cu 2+, confirming further that change in the optical properties of gold nanotriangles in the presence of reduced mercuric ions is solely due to the strong amalgamation tendency of mercury metal.

Original languageEnglish (US)
Pages (from-to)3083-3090
Number of pages8
JournalAnalyst
Volume137
Issue number13
DOIs
StatePublished - Jul 7 2012

Fingerprint

Gold
Mercury
gold
Ions
ion
Cymbopogon
Mercury (metal)
Metals
optical property
Optical properties
metal
Environmental Pollutants
High resolution transmission electron microscopy
Metal ions
Absorption spectra
Transmission Electron Microscopy
detection
Health
transmission electron microscopy
Temperature

ASJC Scopus subject areas

  • Analytical Chemistry
  • Spectroscopy
  • Electrochemistry
  • Biochemistry
  • Environmental Chemistry

Cite this

Ultra-low level optical detection of mercuric ions using biogenic gold nanotriangles. / Singh, Amit; Pasricha, Renu; Sastry, Murali.

In: Analyst, Vol. 137, No. 13, 07.07.2012, p. 3083-3090.

Research output: Contribution to journalArticle

Singh, Amit ; Pasricha, Renu ; Sastry, Murali. / Ultra-low level optical detection of mercuric ions using biogenic gold nanotriangles. In: Analyst. 2012 ; Vol. 137, No. 13. pp. 3083-3090.
@article{9d619a08fa0d4e8f8d001c242794f5d3,
title = "Ultra-low level optical detection of mercuric ions using biogenic gold nanotriangles",
abstract = "Mercury is a serious environmental pollutant known to have detrimental health effects in all life forms. Here, we report the use of biologically synthesized aqueous gold nanotriangles for sensitive and selective optical detection of femto-molar levels of mercury ions by exploiting the high amalgamation tendency of mercury metal towards gold. Aqueous chloroaurate ions were reduced using lemongrass (Cymbopogon flexuosus) leaf extract at room temperature to form gold nanotriangles. Mercuric (Hg 2+) ions were reduced in the presence of these triangles to facilitate amalgamation and the optical properties were monitored. We observe a significant change in the longitudinal plasmon absorption band of the nanotriangles even at femto-molar concentrations of mercuric ions. High-resolution transmission electron microscopy confirms changes in particle morphology at such low concentrations. This protocol shows no sensitivity to other environmentally relevant metal ions, including Pb 2+, Zn 2+, Cd 2+, Fe 2+, Ni 2+, Sr 2+, Ca 2+, Mn 2+, and Cu 2+, confirming further that change in the optical properties of gold nanotriangles in the presence of reduced mercuric ions is solely due to the strong amalgamation tendency of mercury metal.",
author = "Amit Singh and Renu Pasricha and Murali Sastry",
year = "2012",
month = "7",
day = "7",
doi = "10.1039/c2an35162e",
language = "English (US)",
volume = "137",
pages = "3083--3090",
journal = "The Analyst",
issn = "0003-2654",
publisher = "Royal Society of Chemistry",
number = "13",

}

TY - JOUR

T1 - Ultra-low level optical detection of mercuric ions using biogenic gold nanotriangles

AU - Singh, Amit

AU - Pasricha, Renu

AU - Sastry, Murali

PY - 2012/7/7

Y1 - 2012/7/7

N2 - Mercury is a serious environmental pollutant known to have detrimental health effects in all life forms. Here, we report the use of biologically synthesized aqueous gold nanotriangles for sensitive and selective optical detection of femto-molar levels of mercury ions by exploiting the high amalgamation tendency of mercury metal towards gold. Aqueous chloroaurate ions were reduced using lemongrass (Cymbopogon flexuosus) leaf extract at room temperature to form gold nanotriangles. Mercuric (Hg 2+) ions were reduced in the presence of these triangles to facilitate amalgamation and the optical properties were monitored. We observe a significant change in the longitudinal plasmon absorption band of the nanotriangles even at femto-molar concentrations of mercuric ions. High-resolution transmission electron microscopy confirms changes in particle morphology at such low concentrations. This protocol shows no sensitivity to other environmentally relevant metal ions, including Pb 2+, Zn 2+, Cd 2+, Fe 2+, Ni 2+, Sr 2+, Ca 2+, Mn 2+, and Cu 2+, confirming further that change in the optical properties of gold nanotriangles in the presence of reduced mercuric ions is solely due to the strong amalgamation tendency of mercury metal.

AB - Mercury is a serious environmental pollutant known to have detrimental health effects in all life forms. Here, we report the use of biologically synthesized aqueous gold nanotriangles for sensitive and selective optical detection of femto-molar levels of mercury ions by exploiting the high amalgamation tendency of mercury metal towards gold. Aqueous chloroaurate ions were reduced using lemongrass (Cymbopogon flexuosus) leaf extract at room temperature to form gold nanotriangles. Mercuric (Hg 2+) ions were reduced in the presence of these triangles to facilitate amalgamation and the optical properties were monitored. We observe a significant change in the longitudinal plasmon absorption band of the nanotriangles even at femto-molar concentrations of mercuric ions. High-resolution transmission electron microscopy confirms changes in particle morphology at such low concentrations. This protocol shows no sensitivity to other environmentally relevant metal ions, including Pb 2+, Zn 2+, Cd 2+, Fe 2+, Ni 2+, Sr 2+, Ca 2+, Mn 2+, and Cu 2+, confirming further that change in the optical properties of gold nanotriangles in the presence of reduced mercuric ions is solely due to the strong amalgamation tendency of mercury metal.

UR - http://www.scopus.com/inward/record.url?scp=84862232539&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84862232539&partnerID=8YFLogxK

U2 - 10.1039/c2an35162e

DO - 10.1039/c2an35162e

M3 - Article

VL - 137

SP - 3083

EP - 3090

JO - The Analyst

JF - The Analyst

SN - 0003-2654

IS - 13

ER -