Quantitative simultaneous determination of pentoxifylline and paracetamol in drug and biological samples at graphene nanoflakes modified electrode

Simultaneous voltammetry determination of pentoxifylline (PTX) and paracetamol (PAR) were investi- gated by using graphene nanoflakes modified glassy carbon electrode (GrNF/GCE) in drug and biological samples. The synthesized flake was characterized using various analytical methods and the electron trans- fer behavior of GrNF was confirmed by CV and EIS techniques. Electrocatalytic oxidation of PTX and PAR at GrNF/GCE occurred at a potential of +1.220 V and + 0.190 V. The peak to peak separation (900 mV) was obtained for PTX and PAR at GrNF/GCE using DPV method. Amperometry technique was carried out to measure the current response of PTX and PAR and its dynamic ranges from 0.2 × 10−8–300 × 10−6 M (0.9938) and 0.1 × 10−8–150 × 10−6 M (0.9982). The LOD of PTX and PAR were determined to be 0.75 and
0.43 nM (S/N = 3), respectively. This system provides high-level sensitivity in the presence of an excess concentration of easily oxidizable interfering biological molecules and it shows a better reproducibility and repeatability. The present system has been effectively applied for the PTX and PAR determination in real samples.