Selective Electroanalysis of Ascorbic Acid Using a Nickel Hexacyanoferrate and Poly(3,4‐ethylenedioxythiophene) Hybrid Film Modified Electrode

Abstract

The mixed-valent nickel hexacyanoferrate (NiHCF) and poly(3,4-ethylenedioxythiophene) (PEDOT) hybrid film (NiHCF-PEDOT) was prepared on a glassy carbon electrode (GCE) by multiple scan cyclic voltammetry. The films were characterized using atomic force microscopy, field emission scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and electrochemical impedance spectroscopy (AC impedance). The advantages of these films were demonstrated for the detection of ascorbic acid (AA) using cyclic voltammetry and amperometric techniques. The electrocatalytic oxidation of AA at different electrode surfaces, such as the bare GCE, the NiHCF/ GCE, and the NiHCF-PEDOT/GCE modified electrodes, was determined in phosphate buffer solution (pH 7). The AA electrochemical sensor exhibited a linear response from 5 Â 10 À6 to 1.5 Â 10 À4 M (R 2 ¼ 0.9973) and from 1.55 Â 10 À4 to 3 Â 10 À4 M (R 2 ¼ 0.9983), detection limit ¼ 1 Â 10 À6 M, with a fast response time (3 s) for AA determination. In addition, the NiHCF-PEDOT/GCE was advantageous in terms of its simple preparation, specificity, stability and reproducibility.

A Novel Electrochemical Sensor Based on a Mixed Diazonium/PEDOT Surface Functionalization for the Simultaneous Assay of Ascorbic and Uric Acids. Towards an Improvement in Amperometric Response Stability

“…The drawbacks of all these methods are mainly related to their cost and their complex experimental protocols which usually require sample pretreatment and thus a consequent preparation time. In the last two decades, electrochemical methods have been envisaged as an interesting alternative because of their specific advantages: simplicity, low cost, fast analysis and good selectivity 21, 22. However, a major problem arises due to AA and UA slow electrochemical kinetics which induce the need for high overpotentials on most common electrode materials (glassy carbon, gold, platinum…) 23–25.…”

New Robust Redox and Conducting Polymer Modified Electrodes for Ascorbate Sensing and Glucose Biosensing

“…PEDOT has been used in various electrode architectures for ascorbate detection, e.g. PEDOT‐modified gold, platinum and glassy carbon electrodes 15–17, PEDOT/nickel hexacyanoferrate hybrid films 18 or in films containing MWCNTs together with PEDOT 19. Other PEDOT‐based sensors were developed for the detection of NADH 20, H 2 O 2 21 and cysteine 22.…”

Effect of Electrostatic Interaction on Electrodeposition of Nickel Hexacyanoferrate with Functional MWCNTs and Their Application for the Determination of Persulfate and Tannic Acid

“…The AFCNT‐coated electrode was successfully prepared after placing in oven at 80 °C for 15 min. The Inset of Figure 2A showed the electrodeposited of 1 mM nickel(II) with 1 mM hexacyanoferrate (NiHCF film) onto AFCNT/GCE in 0.2 M LiClO 4 solution between −0.4 and +1.0 V at a scan rate of 0.05 V/s for ten cycles by electrostatic interaction 34. Further the NiHCF‐AFCNT/GCE was washed with deionized water and dried for 5 minutes.…”