posted on 2021-12-31, 14:35authored byOlalla Calvo-Lozano, Miquel Sierra, Maria Soler, Maria Carmen Estévez, Luis Chiscano-Camón, Adolfo Ruiz-Sanmartin, Juan Carlos Ruiz-Rodriguez, Ricard Ferrer, Juan José González-López, Juliana Esperalba, Candela Fernández-Naval, Leticia Bueno, Ruben López-Aladid, Antoni Torres, Laia Fernández-Barat, Sarah Attoumani, Rémi Charrel, Bruno Coutard, Laura M. Lechuga
Serological tests
are essential for the control and management
of COVID-19 pandemic (diagnostics and surveillance, and epidemiological
and immunity studies). We introduce a direct serological biosensor
assay employing proprietary technology based on plasmonics, which
offers rapid (<15 min) identification and quantification of severe
acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in
clinical samples, without signal amplification. The portable plasmonic
device employs a custom-designed multiantigen (RBD peptide and N protein)
sensor biochip and reaches detection limits in the low ng mL–1 range employing polyclonal antibodies. It has also been implemented
employing the WHO-approved anti-SARS-CoV-2 immunoglobulin standard.
A clinical validation with COVID-19 positive and negative samples
(n = 120) demonstrates its excellent diagnostic sensitivity
(99%) and specificity (100%). This positions our biosensor as an accurate
and easy-to-use diagnostics tool for rapid and reliable COVID-19 serology
to be employed both at laboratory and decentralized settings for the
disease management and for the evaluation of immunological status
during vaccination or treatment.