Title:Electrochemical Sensing of Vitamin C Using Graphene/Poly-Thionine
Composite Film Modified Electrode
Volume: 16
Issue: 1
Author(s): Ridhu Varshini Murugan, Vasanth Magesh, K. Vijayalakshmi, Raji Atchudan, Sandeep Arya and Ashok K. Sundramoorthy*
Affiliation:
- Centre for Nano-Biosensors, Department of Prosthodontics,
Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha
University, Poonamallee High Road, Velappanchavadi, Chennai, 600077, Tamil Nadu, India
Keywords:
Graphene, poly-thionine, ascorbic acid, electrochemical method, sensor, poly-thionine/graphene composite.
Abstract:
Background: Gastric irritation and kidney problems occur due to excess ascorbic acid
content, whereas the lack of ascorbic acid in the human body leads to poor wound healing, muscle
degeneration, and anemia.
Objectives: Herein, we report the development of an electrochemical sensor for the detection of
ascorbic acid using poly-thionine/ graphene (P-Th/Gr) modified glassy carbon electrode (GCE) in
0.1 M phosphate buffer solution (PBS) (pH 7.4). Electrostatically fused graphene affixed with
poly-thionine was successfully illustrated for effective voltammetric sensing of ascorbic acid.
Methodology: FE-SEM indicated the blended edge of a 2D graphene sheet with a deposited thin
layer of polymer, which confirmed the formation of a poly-thionine/graphene composite. The cyclic
voltammetry (CV) technique was utilized for the electrochemical assay of ascorbic acid (AsA,
Vitamin C).
Results: With the increased concentrations of AsA, the oxidation peak current of ascorbic acid increased
at 0.0 V, and the overpotential showed a decrease compared to bare GCE. The effect of
scan rate on cyclic voltammograms was recorded with 500 μM of ascorbic acid from 10 mV/s to
250 mV/s, which indicated that AsA oxidation is a diffusion-controlled process on poly-thionine/
graphene-modified electrode.
Conclusion: It was concluded that a poly-thionine/graphene composite-based sensor could be useful
for the determination of ascorbic acid in various biological samples.