Enhanced conductivity of a glassy carbon electrode modified with a graphene-doped film of layered double hydroxides for selectively sensing of dopamine

A strategy is presented for doping graphene into layered double hydroxide films (LDHs) as a means of improving charge transport of the LDH film in a modified glassy carbon electrode. This result in an enhanced electrocatalytic current for dopamine (DA) and a good separation of the potentials of DA, uric acid and ascorbic acid. Under selected conditions, the square wave voltammetric response of the electrode to DA is linear in the concentration range from 1.0 to 199 mu M even in the presence of 0.1 mM ascorbic acid, and the detection limit is 0.3 mu M at a signal-to-noise ratio of 3. The method was applied to the determination of DA in pharmaceutical injections with satisfactory results.