2. ENVIRONMENTAL ChEMISTRy & TEChNOLOGy 2.1. Lectures

Chem. Listy, 102, s265–s1311 (2008) Environmental Chemistry & Technology
improvements in LOD and limits of linearity (LOL) were
observed upon increasing or decreasing the accumulation
time, respectively.
Fig. 1. ASV for solutions containing 1 ppm Pb, 3 ppm hg and
varying Cd: (a) 1, (b) 3, (c) 5, (d) 10 ppm
Fig. 2. ASV for solutions containing 1 ppm Cd, 3 ppm hg and
varying Pb: (a) 1, (b) 3, (c) 5, (d) 10 ppm
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Fig. 3. ASV for solutions containing 1 ppm Cd, 1 ppm Pb and
varying hg: (a) 3, (b) 5, (c) 10, (d) 20 ppm
S i m u l t a n e o u s A n a l y s i s
When two or three metals studied in this project are present
in the same solution, well resolved peaks with characteristic
potentials corresponding to specific metal species are
observed as shown in Figs. 1., 2. and 3.
Although linearity between peak height and concentration
is maintained, careful inspection of individual peaks
revealed that sensitivity decreases when the three metal ions
co-exist. Moreover, as the concentration of one metal increases,
the current signal for the other two decreases. This is
presumably due to competition for binding sites among the
metal ions and their varying affinities to carboxylate groups
in pectic acid.
Acknowledgement (This work has been supported by the
Ministry of Development of Brunei Darussalam).
REFEREnCES
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3. Ghiaci M., Rezaei B., Kalbasi R. J.: Talanta 73, 37
(2007).