عنوان مجله
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Analytical and Bioanalytical Electrochemistry
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چکیده
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Abstract- Based on the results of the complexation reaction between 1-acenaphthoquinone 1-thiosemicarbazone (L) and some metal ions in methanol, it was found that the ligand forms
a stable 1:1 complex with Ni2+ ions among the range of ions tested. Accordingly, this hydrazone
derivative was chosen and evaluated as an ionophore for use in the construction of polymeric
membrane sensors with selectivity towards Ni ions. The resulting membrane electrode, under
optimal conditions, had a Nernstian slope of 29.5±0.2 mV/decade over a wide concentration
window of 1.0×10-6-1.0×10-1 M, and its limit of detection was as low as 5.0×10 M. The
electrode had very good selectivity coefficients for other commonly occurring cations in its
response range. The proposed potentiometric sensors possess response times of 10 sec, good
reversibility, and are applicable for over 12 weeks after their first use. The response of the
membrane sensor was pH-independent in the pH range of 5.0–8.0, and it was used in the
analysis of nickel ions concertation in real water samples with satisfactory results. The
electrode was also used in the potentiometric titration of nickel ions using a standard
ethylenediaminetetraacetic acid (EDTA) solution at pH=6.0.
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