Flow-Injection Amperometric Determination of Glucose Using Nickel Oxide-Cobalt (II,III) Oxide and Nickel Oxide-Copper Nanoparticle Modified Pencil Graphite Electrodes

Abstract

This study features an enzyme-free amperometric determination of glucose with flow injection analysis (FIA) using pencil graphite electrodes (PGEs) modified with nickel oxide-cobalt (II,III) oxide (NiO-Co₃O₄/PGE) and nickel oxide-copper nanoparticle (NiO-CuNPs/PGE). Both modified PGEs exhibited excellent electrocatalytic activity toward oxidation of glucose in strong alkaline media since they enhanced the peak current compared with the bare PGE and single metal oxide- or metal nanoparticle-modified PGEs. Flow-injection (FI) amperometry showed the linear response range, the limit of detection and sensitivity for NiO-Co₃O₄/PGE and NiO-CuNPs/PGE were 1.0–1000 µM, 0.23 µM and 586 µA mM⁻¹ cm⁻², and 0.10–250 µM, 0.03 µM and 949 µA mM⁻¹ cm⁻², respectively. Glucose was determined in real samples with good accuracy and precision.

Keywords:

• Amperometry
• pencil graphite electrode
• flow injection analysis
• cyclic voltammetry
• electrochemical impedance spectroscopy
• glucose

Additional information

Funding

This work was funded by the Scientific Research Coordination Unit at Çanakkale Onsekiz Mart University (Project number: FBA-2019-2743).