Stable determination of paracetamol in the presence of uric acid in human urine sample using melamine grafted graphene modified electrode

• Electrochemically reduced graphene oxide on aminotriazine grafted GCE was prepared.
• Stable determination of paracetamol in the presence of uric acid was demonstrated.
• Selective determination of PA in the presence of 50-fold excess UA was achieved.
• Using amperometry, detection of 40 nmol/L PA was obtained.
• Practical application was demonstrated in human urine samples.

Electrochemically reduced graphene oxide (ERGO) on aminotriazine (AT) grafted glassy carbon (AT/GC) electrode was prepared by electrochemical reduction of graphene oxide (GO) attached through 2,4-diamino-1,3,5-triazine on GC electrode and the resulting electrode was utilized for the selective determination of paracetamol (PA) in the presence of higher concentration uric acid (UA). The GO attached on AT/GC (GO/AT/GC) and the ERGO films on AT/GC (ERGO/AT/GC) electrodes were characterized by scanning electron microscopy (SEM), Raman spectroscopy and cyclic voltammetry (CV). The ERGO modified electrode showed excellent electrocatalytic activity towards PA and UA. This electrode not only enhanced the oxidation currents of PA and UA but also shifted their oxidation potentials towards less positive potentials in contrast to bare GC, AT/GC and GO/AT/GC electrodes. Bare and GO modified electrodes failed to separate the voltammetric signals of UA and PA. However, the ERGO/AT/GC electrode successfully separated the voltammetric signals of them in a mixture and hence used for the simultaneous determination. Further, the modified electrode was effectively used for the selective determination of PA in the presence of 50-fold excess of UA. Using amperometry, detection of 40 nM PA was achieved. The current response of PA was increased linearly while increasing its concentration from 4.0 × 10− 8–1.0 × 10− 4 mol/L and the detection limit was found to be 6.8 × 10− 10 mol/L (S/N = 3). The practical application of the present modified electrode was demonstrated by simultaneously determining the concentrations of PA and UA in human urine samples.

Electrochemically reduced graphene oxide fabricated on melamine grafted GCE and then used for the stable determination of paracetamol in the presence of uric acid.Figure optionsDownload as PowerPoint slide