Methylparaben quantification via electrochemical sensor based on reduced graphene oxide decorated with ruthenium nanoparticles

•rGO/RuNPs was synthesized and then immobilized on the surface of GCE by a simple experimental procedure.•The presence of the rGO/RuNPs on GCE provided the increase in charge transfer rate for the methylparaben oxidation (MePa).•Electroanalysis for the quantification of MePa was accurate by statistical comparison with HPLC.

MePa quantification was performed through an electroanalytical method, in which the presence of rGO/RuNPs on GCE surface allowed the increase of the charge transfer rate in the oxidation process of the target molecule. The characterization of the composite material was carried out by TEM, in which the presence of RuNPs with an average diameter of 3.1 ± 0.5 nm dispersed on the surface of rGO was observed.The electroanalytical method developed showed a linear response range of 5.00 × 10−7-3.00 × 10−6 mol L−1 and LOD of 2.40 × 10−7 mol L−1. The results were statistically compared with the data obtained by the official method (HPLC) and shown to be equivalent, which allows discussion upon the use of electroanalytical methods of alternative forms of official analysis methods in cosmetic samples.