Bismuth film electrodes (BiFEs) have a
potential to replace toxic mercury used most frequently for
determination of heavy metals (Cd, Pb, Zn) by anodic
stripping voltammetry. We prepared a graphite disc electrode
(0.5 mm in diameter) from a pencil-lead rod and
developed a nitrogen doped diamond-like carbon (NDLC)
microelectrode array consisting of 50,625 microdiscs with
3 lm in diameter and interelectrode distances of 20 lm on
a highly conductive silicon substrate as a support for
BiFEs. The disc graphite BiFE was used for simultaneous
determination of Pb(II), Cd(II) and Zn(II) by square wave
voltammetry (SWV) in an aqueous solution. We found the
optimum bismuth-to-metal concentration ratio in the
solution to be 20. The dependence of the stripping
responses on the concentration of target metals was linear
in the range from 1 · 10–8 to 1.2 · 10–7 mol/L. Detection
limits 2.4 · 10–9 mol/L for Pb(II), 2.9 · 10–9 mol/L for
Cd(II) and 1.2 · 10–8 mol/L for Zn(II) were estimated. A
bismuth-plated NDLC microelectrode array was used for
Pb(II) determination by differential pulse voltammetry
(DPV) in an aqueous solution. We found that the stripping
current for bismuth-plated NDLC array was linear in the
concentration range of Pb(II) from 2 · 10–8 to 1.2 · 10–7
mol/L. The detection limit 2.2 · 10–8 mol/L was estimated
from a calibration plot