Preparation, Characterization, and Activation of Natural Glassy Carbon Paste Electrodes as New Sensors for Determining the Total Antioxidant Capacity of Plant Extracts

Agnieszka Królicka; Anna Szczurkowska; Paweł Mochalski; Grzegorz Malata

doi:10.3390/membranes12121193

Preparation, Characterization, and Activation of Natural Glassy Carbon Paste Electrodes as New Sensors for Determining the Total Antioxidant Capacity of Plant Extracts

Membranes (Basel). 2022 Nov 26;12(12):1193. doi: 10.3390/membranes12121193.

Authors

Agnieszka Królicka¹, Anna Szczurkowska¹, Paweł Mochalski², Grzegorz Malata¹

Affiliations

¹ Department of Building Materials Technology, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Mickiewicza 30, 30-059 Krakow, Poland.
² Institute of Chemistry, Jan Kochanowski University of Kielce, 25-406 Kielce, Poland.

Abstract

The continuous search for new sensing materials with high recognition capabilities is necessary to improve existing analytical procedures and to develop new ones. Natural glassy carbon and polydimethylsiloxane were shown to be used for the preparation of carbon paste electrodes to employ them in new, voltammetric, green-chemistry-friendly electroanalytical procedures aimed at evaluating the antioxidant capacity of plant extracts, dietary supplements, and hydrolats. The developed electrodes provided well-shaped and reproducible voltammetric signals (RSD = 1%) of the oxidation of epigallocatechin gallate, the main component of many plants and plant-based formulations with antioxidative activity, in the 1-12.5 µM range (DPV mode, LOD = 0.08 µM). If needed, the performance of new carbon paste electrodes can be further enhanced by the introduction of trivalent rare earth oxides to carbon paste to increase its active surface, facilitate electron transfer, and improve the resolution of recorded signals.

Keywords: antioxidants; carbon paste electrodes; catechin; epigallocatechin gallate; glassy carbon; polyphenols; voltammetry.

Grants and funding

Research was carried out using the ‘Financing of research carried out as part of the preparation of a doctoral dissertation at the Faculty of Materials Science and Ceramics at AGH–University of Science and Technology’.