Enhanced Electrochemical Sensor for Electrocatalytic Glucose Analysis in Orange Juices and Milk by the Integration of the Electron‐Withdrawing Substituents on Graphene/Glassy Carbon Electrode
Rahadian Zainul, Illyas Md Isa, Siti Nur Akmar Mohd Yazid, Norhayati Hashim, Sharifah Norain Mohd Sharif, Mohamad Idris Saidin, Mohamad Syahrizal Ahmad, M.Si Suyanta, Yulkifli Amir
Abstract
In this work, a novel electrochemical sensor was developed by electron‐withdrawing substituent modification of 1‐phenyl‐3‐methyl‐4‐(4‐fluorobenzoyl)‐5‐pyrazolone on a graphene‐modified glassy carbon electrode (HPMpFP‐graphene/GCE) for glucose detection. The results of characterizations using a scanning electron microscope, Fourier transform infrared spectroscopy, Raman spectroscopy, and nuclear magnetic resonance spectroscopy showed the successful fabrication of HPMpFP‐graphene nanocomposite, which served as an electroactive probe for glucose detection. The electron transfer ability of HPMpFBP‐graphene/GCE has been successfully revealed using cyclic voltammetry and electrochemical impedance spectroscopy results. The good electrochemical performance was shown by well‐defined peak currents of square wave voltammetry under various parameters, including pH, HPMpFP and graphene composition, and scan rate effect. A high electrochemically evaluated surface area using chronoamperometry suggested that the present glucose detection response was intensified. The chronoamperometry results at a work potential of 0.4 V presented a wide linear range of 1 × 10 3 –90 µ M and 88–1 µ M with 0.74 µ M (S/N = 3) as the detection limit. An acceptable recovery has been revealed in the real sample analysis. The electrochemical sensing behaviour of the composite indicates that it may be a promising candidate for a glucose sensor and it significantly extends the range of applications in the electrochemical field.