Development of Ni-ZnO-ACE-2 peptide hybrids as electrochemical devices for SARS-CoV-2 spike protein detection

Freddy A Nunez; Marcos R de A Silva; Eduardo M Cilli; Sarah T R Brandão; Martin Müller; Dieter Fischer; Quinn A Besford; Wendel A Alves

doi:10.1016/j.bioelechem.2025.108899

Development of Ni-ZnO-ACE-2 peptide hybrids as electrochemical devices for SARS-CoV-2 spike protein detection

Bioelectrochemistry. 2025 Jan 4:163:108899. doi: 10.1016/j.bioelechem.2025.108899. Online ahead of print.

Authors

Freddy A Nunez¹, Marcos R de A Silva², Eduardo M Cilli³, Sarah T R Brandão³, Martin Müller⁴, Dieter Fischer⁴, Quinn A Besford⁵, Wendel A Alves⁶

Affiliations

¹ Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, São Paulo 09210-580, Brazil; Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany.
² Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, São Paulo 09210-580, Brazil.
³ Universidade Estadual Paulista (UNESP), Institute of Chemistry, Araraquara, São Paulo 14800-060, Brazil.
⁴ Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany.
⁵ Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Str. 6, 01069 Dresden, Germany. Electronic address: besford@ipfdd.de.
⁶ Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, São Paulo 09210-580, Brazil. Electronic address: wendel.alves@ufabc.edu.br.

PMID: 39793516
DOI: 10.1016/j.bioelechem.2025.108899

Abstract

Owing to fast SARS-CoV-2 mutations, biosensors employing antibodies as biorecognition elements have presented problems with sensitivity and accuracy. To face these challenges, antibodies can be replaced with the human angiotensin converting enzyme 2 (ACE-2), where it has been shown that the affinity between ACE-2 and the receptor binding domain (RBD) increases with the emergence of new variants. Herein, we report on Ni-doped ZnO nanorod electrochemical biosensors employing an ACE-2 peptide (IEEQAKTFLDKFNHEAEDLFYQS-NH₂) as a biorecognition element for detecting Spike (S) Wild-Type (WT) protein. The electrode was fully characterized in terms of electrochemical and physical properties. The sensor showed high cross reactivity with Spike protein B.1.1.7 and Spike protein B.1.351. Still, there was no cross reactivity with the Nucleocapsid protein WT, showing that the biosensor can identify ancestral WT S protein and S protein variants of concern. The device exhibited a LOD of 60.13 ng mL^-1 across an S protein WT concentration range from 200 ng mL^-1 to 1000 ng mL^-1 and a LOQ of 182.22 ng mL^-1. The calculated sensitivity and specificity were 88.88 and 100 %, respectively. These results proved that the Ni-ZnO sensor has promising prospects for SARS-CoV-2 detection and diagnosis of other viruses, employing peptides as biorecognition elements.

Keywords: ACE-2 peptide; COVID-19; Electrochemical biosensor; Ni-ZnO nanorods; SARS-CoV-2; SARS-CoV-2 variants.