Highly sensitive determination of gallic acid based on a Pt nanoparticle decorated polyelectrolyte-functionalized graphene modified electrode

A sensitive voltammetric sensor for gallic acid was fabricated by using a poly(diallyldimethylammonium chloride) (PDDA)-functionalized graphene supported platinum nanoparticle nanocomposite (PDDA–GR–Pt) modified glassy carbon electrode. The nanocomposite was characterized using UV-vis spectra, transmission electron microscopy (TEM) and X-ray diffraction (XRD). This voltammetric sensor exhibited an excellent electrochemical response for gallic acid. The electrode process of gallic acid was investigated in detail and some dynamics parameters were calculated. Under optimum conditions by square wave voltammetry (SWV), a good linear relationship was obtained between peak currents and gallic acid concentrations in the wider range of 3 × 10−8 to 1 × 10−6 mol L−1 with a lower detection limit of 7 × 10−9 mol L−1 (S/N = 3). In addition, the proposed voltammetric method was successfully applied to test gallic acid in real samples with good results.