Emi Norzehan Mohamad Mahbob, Mohamad Syahrizal Ahmad, Illyas Md Isa, Norhayati Hashim, Anwar Ul-Hamid, Mohamad Idris Saidin, Suyanta, Sofian Ibrahim
Square wave voltammetry, cyclic voltammetry, chronocoulometry, and electrochemical impedance spectroscopy were employed to assess ascorbic acid’s electrochemical behavior in multiwalled carbon nanotubes (MWCNTs)/carbon paste electrode (CPE) modified by 1-phenyl-3-methyl-4-metafluorobenzoyl-5-pyrazolone (HPMmFBP). The ascorbic acid’s irreversible oxidation peak appeared at approximately 0.5 V. The shifting of the peak potential at the pH range of 6.0–8.4 showed the involvement of protons in the ascorbic acid oxidation. Moreover, the shifting of the peak potential with scan rate in the range of 0.07–0.4 V/s confirmed that the oxidation reaction was irreversible. Under optimized conditions, the oxidative peak current showed linear dependence on the ascorbic acid’s concentration between 1 and 1000 μM with limit of detection (LOD) and quantification (LOQ) at 0.1 and 0.34 μM, respectively. HPMmFBP/MWCNT/CPE exhibit good antiinterference ability, reproducibility, repeatability, and stability and was utilized for the accurate and rapid ascorbic acid detection in commercial tablets. Therefore, it has good potential for practical application. © 2024, Universitas Indonesia. All rights reserved.
Department of Chemistry, Faculty of Science and Mathematics, Universiti Pendidikan Sultan Idris, Tanjong Malim, 35900, Malaysia; Faculty of Applied Sciences, Universiti Teknologi MARA, Perak Darul Ridzuan, 35400, Malaysia; Nanotechnology Research Centre, Faculty of Science and Mathematics, Universiti Pendidikan Sultan Idris, Tanjong Malim, 35900, Malaysia; Core Research Facilities, King Fahd University of Petroleum & Minerals, Dhahran, 31261, Saudi Arabia; Department of Chemistry Education, Faculty of Mathematics and Natural Science, Yogyakarta State University, Yogyakarta, 55281, Indonesia; Malaysian Nuclear Agency, Kajang, 43000, Malaysia
