Electrochemical Detection of Ascorbic Acid by Fe₂O₃ Nanoparticles Modified Glassy Carbon Electrode

Background  The article delineates a strategy for detecting ascorbic acid (AA) through the use of iron oxide (Fe₂O₃) nanoparticles on an electrode. The Fe₂O₃ nanoparticles demonstrated effective electrocatalysis in the oxidation of AA, resulting in increased peak currents. The sensor showcased a wide linear detection range, a low detection limit, and high selectivity towards interferents, making it suitable for accurate AA measurement in food analysis and medical diagnostics applications. This emphasizes the potential of Fe₂O₃ nanoparticle-based sensors for precise AA detection. Aim The primary aim of this research is to develop an electrochemical sensing technique for the identification of ascorbic acid, with the use of Fe₂O₃ nanoparticles as the sensing matrix. Materials and methods The synthesis process involved the utilization of FeCl₃.6H₂O, ammonia solution, ethanol, and double-distilled water. FeCl₃.6H₂O was dissolved in ammonia water to produce a brown precipitate for the synthesis of Fe₂O₃ nanoparticles. Subsequently, the brown precipitate underwent hydrothermal treatment at 180 °C, resulting in the formation of a red product. Following centrifugation, washing, and drying steps, Fe₂O₃ nanoparticles were successfully synthesized. These nanoparticles were then utilized to modify the glassy carbon electrode (GCE). Prior to the modification, the GCE underwent polishing and cleaning procedures, after which it was coated with a suspension containing 5 mg of Fe₂O₃ nanoparticles in 10 mL of ethanol. The coated electrode was dried and deemed ready for application in electrochemical sensing. Results The hydrothermal method was employed in this research to synthesize Fe₂O₃ nanoparticles, which were subsequently subjected to a series of experiments to evaluate their electrochemical sensing capabilities. The resulting Fe₂O₃ nanoparticles were determined to possess a high level of purity and a crystalline structure through various analyses, including field emission-scanning electron microscopy (FE-SEM), cyclic voltammetric testing, X-ray diffraction (XRD), energy-dispersive X-ray (EDX) spectroscopy analysis, differential pulse voltammetry (DPV), and the current response of the Fe₂O₃-modified electrode towards ascorbic acid. The morphology of the Fe₂O₃ nanoparticles was observed to be uniform. The synthesized particles successfully fulfilled the study's objective by exhibiting remarkably sensitive and selective sensitivity towards ascorbic acid. Conclusion Our study underscores the potential of utilizing Fe₂O₃ nanoparticle-based electrochemical sensing to detect ascorbic acid, as evidenced by the notably high sensitivity of ascorbic acid towards Fe₂O₃ nanoparticles. The distinctive properties of Fe₂O₃ nanoparticles, which include their large surface area, efficient electron transport, and straightforward manufacturing process, significantly enhance the sensor's performance. Further research is crucial to exploring the wide-ranging applications of the sensor in fields such as food safety, environmental monitoring, and biological diagnostics and to overcome any existing limitations.