Dopamine-functionalized graphene oxide as a high-performance material for biosensing

To study the effectiveness of 1,2-dihydroxyphenyl moieties in inducing electrocatalytic oxidation of NADH, we combined standard voltammetric techniques with UV-Vis absorption spectroelectrochemistry, which allowed us to measure the variations in composition occurring at the electrode vertical bar solution interface, i.e. to measure the consumption rate of NADH.

We describe a nanocomposite material for the electrochemical detection of beta-nicotinamide adenine dinucleotide (NADH), a coenzyme involved in redox reactions of all living cells and in the detection of many organic species by electrochemical biosensors. The composite is made of nanosheets of electrochemically exfoliated graphene oxide (EGO) covalently functionalized with dopamine (DP) molecules. The EGODP material finally obtained is rich of 1,2-dihydroxyphenyl moieties and is able to detect NADH at a particular low potential value with higher sensitivity with respect to pristine EGO.