Anita Martinović1,* and Njegomir Radić2
1 Department of Chemistry, Faculty of Science and Education, University of
Mostar, Matice hrvatske bb,
Mostar, Bosnia & Herzegovina
2 Department of Chemistry, Faculty of Chemistry and Technology, University of
Split, Teslina 10/V, Split, Croatia
* Corresponding author: E-mail: anita.martinovic@tel.net.ba
Abstract
Optimization and application of simple kinetic potentiometric method for the
determination of D-penicillamine (PEN)
and N-acetyl-L-cysteine (NAC) in pharmaceutical is described. The method was
based on the reaction between thiol and
iodate, in the presence of small quantity of iodide. The changes of potentials,
ΔE, in fixed time interval were measured
with an iodide ion selective electrode versus a double-junction reference
electrode. Good linearity between ΔE and negative
logarithm of analyte concentration is achieved in the range of the studied drugs
concentration from 1.0 × 10–6 to
1.0 × 10–4 M. The limit of detection for PEN is 9.0 × 10–8 M and for NAC is 1.0
× 10–7 M. The applicability of the proposed
method to the determination these thiols in pharmaceutical preparation was
demonstrated by investigating the effect
of potential interferences and by analysis of commercial preparations.
Keywords: D-penicillamine, N-acetyl-L-cysteine, kinetic potentiometry, iodide ion selective electrode