The Malaysian Journal of Analytical Sciences Vol 16
No 2 (2012): 194 – 201
DEVELOPMENT OF A METHOD FOR THE
SPECIATION OF MERCURY IN ENVIRONMENTAL SAMPLE ANALYSIS
(Pembangunan Kaedah Bagi Analisis Penspesian Merkuri Dalam Sampel
Sekitaran)
M. M.
Rahman1*, M. Awang1, A. M. Yusof 2, A. K. H. Wood3, S.
Hamzah3 and A. Shamsiah3
1Department of
Pharmaceutical Chemistry, Faculty of Pharmacy,
International
Islamic University Malaysia, Indera Mahakota, 25200 Kuatan, Pahang, Malaysia.
2Department of
Chemistry, Faculty of Science,
Universiti Teknologi Malaysia, Skudai,
JB, 81310 Malaysia.
3Malaysian
Institute for Nuclear Technology Research (MINT),
Bangi, Kajang, 43000 Malaysia
*Corresponding author: mdrahman@iium.edu.my
Abstract
Trace
concentrations of mercury in water samples were determined by a method
involving a simple and rapid procedure connecting the flow-injection
inductively coupled plasma mass spectrometry (FI-ICP-MS) and graphite furnace
atomic absorption spectrometry (GFAAS) techniques. Mercury vapor, generated by
sodium borohydride as the reductant, was stabilized by potassium dichromate (K2Cr2O7),
then released by controlled heating and detected by FI-ICP-MS. A flow injection
sample introduction system with time based injection was used and the
sensitivity was found to be proportional to the mass of mercury introduced. Methyl
mercury (II) was preconcentrated using the ammoniumpyrrolidindithiocarbamate
(APDTC)-chloroform extraction procedure and the chloroform extract was
introduced into the graphite tube. A linear calibration graph was obtained for
5 -150 ng mercury in 2.5 ml of chloroform extract. Because of the high
stability of MeHg (II)-APDTC complexes, it is possible to evaporate the extract
in order to obtain a crystalline powder to be dissolved with a few micro liters
of chloroform enacting MeHg (II) and Hg (II) can be detected at sub-nanogram
levels.
Keywords: Methyl mercury, Flow Injection-Inductively Coupled
Plasma Mass Spectrometry, Graphite Furnace Atomic Spectrometry and ammoniumpyrrolidindithiocarbamate
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