Highly sensitive and simultaneous voltammetric determination of Diclofenac and Piroxicam using graphene ionic liquid modified carbon-ceramic electrode

Carbon ceramic electrodes have been widely used for the electrochemical determination of important biological and pharmaceutical compounds [1, 2]. In the present work, a voltammetric method for simultaneous determination of sodium diclofenac and piroxicam was developed using carbon ceramic electrode modified with grapheme and ionic liquid (1-Ethyl-3-methylimidazolium hexafluorophosphate). The obtained results showed that the voltammetric response of modified electrode improves in comparison with bare carbon ceramic electrode. On the other hand, the possibility simultaneous determination of two mentioned drugs provides using square wave voltammetry after optimization of electrochemical conditions. The proposed method showed linear responses for sodium diclofenac ranging A (0.005-1 µM) and B (1-1000 µM) and for piroxcam ranging A (0.005-1 µM) and B (1-100 µM) at pH 5 (acetate buffer 0.1 M). The detection limits for proposed method was 1.6 nanomolar and 2.5 nanomolar for sodium diclofenac and piroxicam, respectively. The proposed method has been successfully used for the determination of these drugs in real samples.