Coupled graphene oxide with hybrid metallic nanoparticles as potential electrochemical biosensors for precise detection of ascorbic acid within blood.

Ascorbic acid (AA) as an essential biological molecule for proper performance of body can act as a biological metric for precise detection of various kinds of disease through measuring the level of oxidative stress; thus its precise/dividable detection is an urgent requirement for development of advanced biosensors. To address this requirement, we decorated well-exfoliated graphene oxide (GO) with Ag and hybrid Ag-Fe3O4 metallic nanoparticles toward precise, real-time and repeatable detection of AA within the blood plasma samples via electrochemical approaches that led to the development of a retrievable biosensor. Outcome of performed evaluations showed that modification of glassy carbon electrode (GCE) with selected additives significantly improved its sensitivity/selectivity. In this matter, the modified GCE with GO-Ag-Fe3O4 showed limit of detection and sensitivity of 74 nM and 1146.8 μA mM-1 cm-2, respectively, within the concentration range of 0.2-60 μM. Additionally, the modified electrode kept 91.23% of its total performance after 15 days of performance and detected the oxidation peak of AA even with present of 50 fold of annoying contents which highlighting its superior stability/selectivity. More importantly, the developed electrode showed recovery range between 96.0 and 104.4% within the human blood plasma samples that confirmed the ideal capability of developed platform for accurate detection of AA within biological fluids.