▎ 摘　　要

Graphene-poly-L-lysine nanosheets (Gr-PLL) were synthesized and fully characterized. Tyrosinase was immobilized on the Gr-PLL nanosheets modified glassy carbon electrode which was employed as an amperometric biosensor for bisphenol A. The obtained biosensor was characterized with scanning electron microscopy and electrochemical impedance spectroscopy. Experimental conditions on the sensing performance of the as-prepared biosensor were investigated. The biosensor displayed a linear response to bisphenol A over a concentration range which spanned from 0.02 mu M to 8.0 mu M with a detection limit of 0.01 mu M (S/N = 3). The biosensor was successfully applied to determine trace amounts of bisphenol A leaching from plastic drinking bottles.