Synthesis of cobalt ferrite and simultaneous determination of ascorbic acid, acetaminophen and caffeine by voltammetric method using cobalt ferrite modified electrode

In the present article, the synthesis of spherical hollow cobalt ferrite and application as an electrode modifier were demonstrated. The synthesis of cobalt ferrite was conducted using carbonaceous microspheres prepared from a glucose solution as a sacrificial template, followed by subsequent heat treatment. The Fe/Co molar ratio in cobalt ferrite depends significantly on the initial Fe/Co molar ratio. The Fe/Co molar ratio as 1/1 could provide the stoichiometric cobalt ferrite (CoFe₂O₄) with a hollow sphere structure and large saturation magnetization. The simultaneous quantification of ascorbic acid (ASA), acetaminophen (ACE), and caffeine (CAF) was performed utilizing the differential pulse anodic stripping voltammetric method with CoFe₂O₄ modified glassy carbon electrode. The detection limits in the linear range of 0.2–4.4 µM are 0.313, 0.267, and 0.226 µM for ASA, ACE, and CAF, respectively. This proposed method enables the simultaneous detection of ASA, ACE, and CAF in pharmaceutical formulations and beverage samples. The determined concentration of the analytes is comparable with that obtained with HPLC.