Electrochemical Sensor Based on Gold Nanoparticles Stabilized in Poly(Allylamine hydrochloride) for Determination of Vanillin

Gold nanoparticles stabilized in poly(allylamine hydrochloride) (AuNP-PAH) were synthesized, characterized and applied in the development of a new sensor for the determination of vanillin by square-wave voltammetry. Under optimized conditions, the calibration curve showed a linear range for vanillin of 0.90 to 15.0 mu molL(-1), with a limit of detection of 55 nmolL(-1). The sensor demonstrated acceptable selectivity and stability, as well as good intra-day and inter-day repeatability and electrode-to-electrode repeatability (with relative standard deviations of 3.5, 4.5 and 3.9%, respectively). The sensor was successfully applied in the determination of vanillin in different commercial samples.