A High sensitive voltammetric sensor for bisphenol A using a nanostructure modified electrode

Bisphenol A is a chemical used in the manufacture of epoxy resins for the lacquer lining of metal food cans, as a monomer of polycarbonates, and the monomer of plastic used in the base paste ofdental sealants [1]. But polycarbonate and epoxy resins, inner surface coating of food and beverage cans, from which BPA can leach into food and environment. The electrochemistry of bisphenol A (BPA) was studied by voltammetric methods at a surfaceof carbon paste electrode modified by a ZnO/CNTs nanocomposite and room-temperature ionic liquid of 1,3-dipropylimidazolium bromide. The ratio of ZnO/CNTs and ionic liquid (IL) on the surface of the electrode has to be controlled carefully because the charging currents. The anodic peaks of BPA and Sudan I in their mixture can be well separated. At pH 7.0 the two peaks are separated ca. 0.47 and 0.70 V, respectively; hence BPA can be determined in the presence ofSudan I and more than 8.7 times current excess of BPA. The peaks current of square wavevoltammograms (SWV) of BPA and Sudan I increased linearly with their concentration in the ranges of 0.002–700 μM BPA and 0.2–800 μM Sudan I. The detection limits for BPA and Sudan I were 9.0 nM and 80 nM, respectively. The modified electrode has been successfully applied for the assay of BPA in food samples. This study provides a simple and easy approach to selectively detect BPA in the presence of Sudan I.

Keywords:

Bisphenol A , ZnO/CNTs , Ionic liquids , Voltammetric analysis