Electrochemical sensor for epinephrine based on a glassy carbon electrode modified with graphene/gold nanocomposites

► A water-soluble GR/Au nanocomposites was synthesized by a chemical co-reduction method. ► A novel electrochemical sensor for epinephrine was fabricated based on the GR/Au nanocomposites. ► This sensor showed high sensitivity in the detection of epinephrine. ► The sensor in real sample analysis was examined in pharmacal injection.