Enhanced Biosensing of Bisphenol A Using a Nanointerface Based on Tyrosinase/Reduced Graphene Oxides Functionalized with Ionic Liquid

Reduced graphene oxide (rGO) nanosheets functionalized with 1,3‐di(4‐amino‐1‐pyridinium) propane tetrafluoroborate ionic liquid (DAPPT) was successfully synthesized and fully characterized. DAPPT‐rGO nanosheets were coated to a glassy carbon electrode (GCE) surface to immobilize tyrosinase (Tyr). The Tyr‐DAPPT‐rGO/GCE was characterized with scanning electronic microscopy and electrochemical impedance spectroscopy. The biosensor shows a linear response to bisphenol A (BPA) in the concentration range of 1.0×10−9∼3.8×10−5 mol L−1. The detection limit was calculated to be 3.5×10−10 mol L−1 (S/N=3). The practical application was demonstrated by determining BPA leaching from commercial plastic drinking bottles.