A modified nanostructured graphene-gold nanoparticle carbon screen-printed electrode for the sensitive voltammetric detection of rutin

This study presents a graphene-gold nanoparticles screen-printed voltammetric sensor for the determination and quantification of rutin in pharmaceutics by means of square-wave voltammetry. The cyclic voltammetry electrochemical studies have demonstrated that the sensor has a large active surface and the transfer of electrons is facilitated by the nanostructured materials in the sensing material. To increase the performance of the sensor to rutin, the following experimental conditions were optimized: the detection method, the nature of the electrolyte solution and the pH. In optimum conditions of square-wave voltammetry in acetate buffer solution of pH 5.0, the sensor allows the detection of rutin on a potential of 0.44 V vs. Ag/AgCl. The current of the anodic peak varies linearly with the rutin concentration ranging in the domain 0.1 × 10−6 to 15 × 10−6 M, with a detection limit of 1.1 × 10−8 M. The nanomaterials-based sensor was effectively used for the quantification of rutin in the pharmaceutical products being characterized by precision, repeatability and great accuracy. Furthermore, the results obtained correspond with those obtained with the standard method and with the amounts indicated by the producer, respectively, having a 99% confidence level.