Hydrogel-Graphene Oxide Nanocomposites as Electrochemical Platform to Simultaneously Determine Dopamine in Presence of Ascorbic Acid Using an Unmodified Glassy Carbon Electrode

PEREYRA, JÉSICA; MARTINEZ, MARÍA; BARBERO, CESAR; BRUNO, MARIANO; ACEVEDO, DIEGO

Journal of Composites Science

mdpi

Lugar: Basilea; Año: 2018 vol. 3

The detection of dopamine, an important neurotransmitter in the central nervous system,is relevant because low levels of dopamine can cause brain disorders. Here, a novel electrochemicalplatform made of a hydrogel?graphene oxide nanocomposite was employed to electrochemicallydetermine simultaneously dopamine (DA) and ascorbic acid (AA). Unlike previous work, where thebase electrode is modified, the active material (graphene oxide, GO) was dispersed in the hydrogelmatrix, making an active nanocomposite where the electrochemical detection occurs. The GO,hydrogel and nanocomposite synthesis is described. Dynamic Light Scattering, UV-visible andFTIR spectroscopies showed that the synthesized GO nanoparticles present 480 nm of diagonalsize and a few sheets in height. Moreover, the polymer swelling, the adsorption capacity and therelease kinetic of DA and AA were evaluated. The nanocomposite showed lower swelling capacity,higher DA partition coefficient and faster DA release rate than in the hydrogel. The electrochemicalmeasurement proved that both materials can be employed to determine DA and AA. Additionally,the nanocomposite platform allowed the simultaneous determination of both molecules showingtwo well separated anodic peaks. This result demonstrates the importance of the incorporation of thenanomaterial inside of the hydrogel and proves that the nanocomposite can be used as a platform inan electrochemical device to determinate DA using an unmodified glassy carbon electrode.