The direct electrochemistry of diclofenac (DCF) at a surface of modified carbon paste electrode (CPE) was
described. The electrode was modified with multiwall carbon nanotubes (MWCNTs) and 1-butyl-3methylimidazolium
hexafluoro phosphate as a binder. The oxidation peak potential of the DCF at a surface of
the ionic liquid carbon nanotubes paste electrode (IL/CNTPE) appeared at 750 mV that was about 70 mV lower
than the oxidation peak potential at the surface of the traditional carbon paste electrode under similar condition.
Under the optimized conditions at pH 7.0, the peak current was linear to DCF concentrations over the concentration
range of 0.3–750 μmol L
−1
, using square wave voltammetry (SWV). The detection limit was 0.09 μmol L
.
The proposed method was successfully applied to the determination of DCF in both pharmaceutical and patient
urine samples.
