Industrial waste reuse: An alternative source to reduced graphene oxide for preparing electrochemical sensors

Development of sustainable electroanalytical platforms based on recovering approaches has great importance, once that they aim to minimize waste and increase reusing/recycling efforts, as well as engage the circular economy. This work converted an industrial waste carbon source to a recycled reduced graphene oxide (r-rGO) using a cost effective wide scale synthesis. The r-rGO was characterized by SEM, XRD, FTIR, and Raman spec-troscopy techniques and as a proof-of-concept the new material was applied as electrode modifier for paracet-amol (PAR) electroanalytical determination in tablets. The simple, easy and rapid technique of drop casting a suspension solution of r-rGO, was used to prepare the surface of a chemically modified glassy carbon electrode (GCE) forming a r-rGO/GCE sensor. Differential pulse voltammetry (DPV) was optimized and applied success-fully in the paracetamol determination with a linear range of 60-500 mu mol L-1 and detection limit of 0.28 mu mol L-1. Then, two commercialy avaliable paracetamol tablets were used, with a minimum sample preparation, achieving recoveries of 99.43% and 100.47%. A HPLC (high performance liquid chromatography) comparative method was performed obtaining recoveries of 100.92% and 101.00%. Finally, the obtained results demonstrate that the r-rGO/GCE sensor can be a promising alternative for the quantitative determination of PAR in phar-maceutical formulations.