ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

A low-cost electrochemical biosensor for vaccinia virus using pencil graphite electrodes modified with poly(hydroxybenzamide)

Rafael Mendes Coelho, Andressa de Oliveira Almeida, Priscila Izabela Soares, Kamila Lorene Soares Rocha, Danilo Bretas de Oliveira, Arnaldo César Pereira, Diego Leoni Franco, and Lucas Franco Ferreira

Institute of Science and Technology, Federal University of the Jequitinhonha and Mucuri Valleys, UFVJM, Diamantina, Brazil

E-mail: lucas.franco@ict.ufvjm.edu.br

Received: 15 April 2023  Accepted: 10 September 2023

Abstract:

Vaccinia is caused by the vaccinia virus and affects thousands of people, particularly in underprivileged communities, in over 100 countries worldwide. In Brazil, more than 10,000 cases are registered between January and June 2023, with some resulting in fatalities. This study investigates the use of pencil graphite electrodes (PGEs) modified with polymeric films from 2-hydroxybenzamide (2HB) and 4-hydroxybenzamide (4HB) to develop a biosensor to diagnose vaccinia virus (VACV) infection. Polymeric films were produced by electropolymerization of the respective monomers using cyclic voltammetry. The modified electrodes showed a reduced response to the potassium ferro/ferricyanide solution and increased charge transfer resistance (R_ct). Two recognition strategies have been proposed: immobilizing VACV for detecting anti-VACV antibodies and immobilizing anti-VACV for virus detection. In the detection of anti-VACV, R_ct increased by approximately 162% for PGE/poly(2HB) and 55% for PGE/poly(4HB), with no significant changes observed for non-specific antibodies. For VACV detection, the R_ct response increased by 30 and 190% in the presence of the viral particles for PGE/poly(2HB) and PGE/poly(4HB), respectively. The biosensors displayed a significant increase in R_ct response in the presence of viral particles, demonstrating their potential for detecting viral antigens or antibodies. PGE/poly(2HB) and PGE/poly(4HB) were found to be suitable for detecting anti-VACV and the vaccinia virus itself, respectively, using the applied method. These findings highlight the versatility of the biosensor for a wide range of applications, including diagnostic tests and vaccine quality control, and emphasize its potential for VACV diagnosis. A biosensor that detects both vaccinia antigens and viruses can aid in monitoring immune responses, diagnosing infections, ensuring vaccine safety, and tracking outbreaks.

Graphical abstract

Keywords: 2-Hydroxybenzamide; 4-Hydroxybenzamide; Electropolymerization; Immunosensor; Impedimetric detection; Vaccinia virus

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-03073-y

Chemical Papers 77 (12) 7563–7575 (2023)