ZnO/GO Composite as Electrochemical Sensor for GABA Detection

Gamma-aminobutyric acid (GABA) is a crucial inhibitory neurotransmitter that decreases nervous system activity by inhibiting signal transmission across synapses. Imbalances in GABA levels are linked to neurological diseases. This study developed an electrochemical sensor for detecting GABA using a ZnO/GO composite as the sensing material. Graphene oxide (GO) was synthesized via a modified Hummer’s method, while nanoparticulate zinc oxide (ZnO) was prepared using a solution combustion method. X-ray diffraction and morphological analysis showed crumpled graphene oxide sheets stacked into multilayers and a single phase of wurtzite-structured ZnO with a crystallite size of 69.37 nm; however, the particles tended to cluster together into larger agglomerates, leading to a reduction in specific surface area. The ZnO/GO composite demonstrated synergistic electrocatalytic activity. Cyclic voltammetry in GABA solutions (0.1 to 1000 µM) revealed distinctive oxidation and reduction peaks with sensitivity ranged from 0.0184 to 0.6629 µA mM -1 mm -2 . Despite moderate electrocatalytic performance, the ZnO/graphene oxide composite shows potential as a GABA sensing material.