Bifunctional Au@Pt/Au nanoparticles as electrochemiluminescence signaling probes for SARS-CoV-2 detection
Ana M. Villa-Manso, Tamara Guerrero-Esteban, F. Pariente, Celia Toyos‐Rodríguez, Alfredo de la Escosura‐Muñiz, Mónica Revenga‐Parra, Cristina Gutiérrez‐Sánchez, Encarnación Lorenzo
Abstract
A novel immunosensor based on electrochemiluminescence resonance energy transfer (ECL-RET) for the sensitive determination of N protein of the SARS-CoV-2 coronavirus is described. For this purpose, bifunctional [email protected] nanoparticles composed of a Pt-coated Au core and finally decorated with small Au inlays ([email protected]/Au NPs) have been synthesized to act as ECL acceptor, using [Ru (bpy)3]2+ as ECL donor. These nanoparticles are efficient signaling probes in the immunosensor developed. The proposed ECL-RET immunosensor has a wide linear response to the concentration of N protein of the SARS-CoV-2 coronavirus with a detection limit of 1.27 pg/mL. Moreover, it has a high stability and shows no response to other proteins related to different virus. The immunosensor has achieved the quantification of N protein of the SARS-CoV-2 coronavirus in saliva samples. Results are consistent with those provided by a commercial colorimetric ELISA kit. Therefore, the developed immunosensor provides a feasible and reliable tool for early and effective detection of the virus to protect the population.