Simultaneous and individual determination of seven biochemical species using a glassy carbon electrode modified with a nanocomposite of Pt nanoparticle and graphene by a one-step electrochemical process

Abstract

We propose a sensitive and selective electrochemical approach for simultaneous and individual determination of seven electroactive biochemical species using a modified electrode with a nanocomposite of Pt nanoparticles and reduced graphene oxides (PtNP/rGO). The PtNP/rGO nanocomposite was synthesized and deposited on a glassy carbon electrode (GCE) from Pt⁴⁺ precursors and GO by one-pot electrochemical synthesis, forming PtNP/rGO-GCE. As-prepared PtNP/rGO electrode was characterized by Raman spectroscopy, contact angle measurements, SEM-EDS analysis, and cyclic voltammetry. Compared with bare GCE, Pt electrode, PtNP-GCE, the modified electrode exhibited excellent catalytic activity and large surface area, and rGO-GCE, which enabled sensitive and selective detection of seven biochemical species such as ascorbic acid (AA), dopamine (DA), uric acid (UA), acetaminophen (AP), xanthine (XA), nitrite (NO₂^-), and hypoxanthine (HX) with good voltammetric resolution in differential pulse voltammetric (DPV) measurements. In addition, the electroanalytical performance of the PtNP/rGO-GCE sensor displayed satisfactory reproducibility and stability. Finally, the sensor could be applied for the detection of the seven biochemical species in real samples like human blood serum. Therefore, the PtNP/rGO-GCE can provide one promising platform for the simultaneous detection of redox-active biochemical species in environmental, food, and clinical samples.

Keywords: Electrochemical sensor; Nanocomposite; PtNP/rGO; Redox active biochemical species; Simultaneous detection.