Simultaneous electroanalytical determination of luteolin and rutinusing artificial neural networks (original) (raw)

In this study, we propose an electroanalytical method to quantify simultaneously luteolin and rutin,two flavonoids which are present in a pharmaceutical formulation. The methodology is based on squarewave voltammetry at glassy carbon electrodes modified with multiwalled carbon nanotubes dispersed inpolyethylenimine. Both flavonoids show quasi-reversible surface redox couples in 10% ethanol + 1 mol L−1HClO4aqueous solutions, which are defined in potential regions very close to each other. The adsorptionprocess of flavonoids on the modified electrode surface was carried out using an accumulation potentialof 0.55 V (vs. Ag/AgCl, 3 mol L−1KCl), and an accumulation time of 20 min.Considering that luteolin and rutin electrochemical responses show a high degree of overlapping, weprocessed the electrochemical signals using artificial neural networks. We used a supervised network,feed-forward network with Levenberg-Marquardt back propagation training. Values of 92.6 ± 0.4 and92 ± 1 mg per tablet were determined by the artificial neural networks methodology for luteolin andrutin, respectively. According to values declared by the manufacturer, differences of 7.4 and 8.0% werecalculated for luteolin and rutin, respectively. Results obtained with electroanalytical methodologieswere in very good agreement with those obtained by HPLC.