Electrochemical Sensor for Bisphenol A Based on Tyrosinase/ionic Liquid-graphene Nanointerface

Graphene-1,3-di(4-amino-1-pyridinium) propane tetrafluoroborate ionic liquid nanocomposite (Gr-DAPPT) modified on a glassy carbon electrode and then tyrosinase (Tyr) was immobilized onto the electrode to fabricate a biosensor. Experimental conditions including the volume of Tyr-Gr-DAPPT solution, the applied potential, and pH value were optimized for bisphenol A (BPA) determination. The biosensor exhibited a linear response to BPA in the concentration range from 1.0×10^-9 to 3.8×10^-5 mol/L. The detection limit was calculated to be 3.5×10^-10mol/L (R_SN=3). Practical application of the biosensor was demonstrated by determining BPA leaching from commercial plastic drinking bottles. The result was consistent with that obtained by high performance liquid chromatography