Electrochemical Immunosensors Based on Zinc Oxide Nanorods for Detection of Antibodies Against SARS-CoV-2 Spike Protein in Convalescent and Vaccinated Individuals

• DOI: 10.1021/acsbiomaterials.2c00509
• Publication Date: 2022-09-01T16:52:29Z
• Authors: Freddy A. Nunez; Ana C. H. Castro; Vivian L. de Oliv...; Ariane C. Lima; Jamille R. Oliveira; Giuliana X. de Me...; Greyce L. Sasahara; Keity S. Santos; Alexandre J. C. L...; Wendel A. Alves
• Keywords: Nanorod; Tin oxide

Even after over 2 years of the COVID-19 pandemic, research on rapid, inexpensive, and accurate tests remains essential for controlling avoiding global spread SARS-CoV-2 across planet during a potential reappearance in future waves or regional outbreaks. Assessment serological responses can be beneficial population-level surveillance purposes, supporting development novel vaccines evaluating efficacy different immunization programs. This especially relevant broadly used inactivated whole virus vaccines, such as CoronaVac, which produced lower titers neutralizing antibodies. showed specific groups elderly immunocompromised. We developed an impedimetric biosensor based immobilization recombinant trimeric spike protein (S protein) zinc oxide nanorod (ZnONR)-modified fluorine-doped tin substrates serology testing. Due to electrostatic interactions, negatively charged S was immobilized via physical adsorption. The electrochemical response immunosensor measured at each modification step characterized by scanning electron microscopy techniques. successfully evaluated applicability modified ZnONR electrodes using serum samples from convalescent individuals, CoronaVac-vaccinated with without positive results infection, pre-pandemic healthy volunteers controls. ELISA IgG anti-SARS-CoV-2 performed comparison, anti-RBDs seasonal coronavirus (HCoVs) test specificity detection. No cross-reactivity HCoVs detected immunosensor, more interestingly, sensor presented higher sensitivity when compared negative results. demonstrate that ZnONRs/spike-modified electrode displayed sensitive convalescents vaccinated shows excellent tool population's assessment monitoring seroconversion seroprevalence.