Simultaneous Voltammetric Determination of Flavanones Using an Electrode Based on Functionalized Single-Walled Carbon Nanotubes and Polyaluminon

Abstract

A glassy carbon electrode (GCE) modified with polyaminobenzene sulfonic acid functionalized single-walled carbon nanotubes (f-SWCNT) and electropolymerized aluminon has been developed for the simultaneous determination of naringin and hesperidin. Polyaluminon has been obtained by potentiodynamic electrolysis in basic medium from 100 µmol L⁻¹ monomer solution by 10-fold potential cycling from 0.1 to 0.8 V at potential scan rate of 100 mV s⁻¹. The polyaluminon-based electrode provides a statistically significant increase in the naringin and hesperidin oxidation currents at the same potentials in comparison to the electrode modified with carbon nanotubes. The electrode has been characterized by scanning electron microscopy (SEM) and electrochemical methods. The polyaluminon-modified electrode has demonstrated a 1.5-fold increase in the effective surface area compared to the f-SWCNT/GCE as well as a 2.1-fold lower electron transfer resistance. The electrooxidation parameters of hesperidin and naringin, including the anodic transfer and diffusion coefficients and number of electrons, have been determined. Differential pulse voltammetry in phosphate buffer (PB) pH 5.0 has been employed for the simultaneous determination of naringin and hesperidin. The linear dynamic ranges from 0.10 to 2.5 and 2.5 to 25 µmol L⁻¹ have been obtained for the both analytes with the detection limits of 0.020 and 0.029 µmol L⁻¹ for naringin and hesperidin, respectively. The method has been employed for the analysis of orange and grapefruit juice.

Keywords:

• Aluminon
• electropolymerization
• flavonoids
• modified electrodes
• voltammetry

Additional information

Funding

The financial support of Russian Foundation for Basic Research [grant No. 18-33-00220-mol_a] is gratefully acknowledged.