Detection of SARS-CoV-2 virus via dynamic light scattering using antibody-gold nanoparticle bioconjugates against viral spike protein

Author(s):Show less -

da Silva, Patricia Bento ; da Silva, Jaqueline Rodrigues ; Rodrigues, Mosar Correa ; Vieira, Julia Augusto ; de Andrade, Ikaro Alves ; Nagata, Tatsuya ; Santos, Alexandre Silva ; da Silva, Sebastiao William ; Oliveira da Rocha, Marcia Cristina ; Bao, Sonia Nair ; Moraes-Vieira, Pedro M. ; Proenca-Modena, Jose ; Angelim, Monara K. C. ; de Souza, Gabriela Fabiano ; Muraro, Stefanie Primon ; Branco de Barros, Andre Luis ; de Souza Martins, Glendara Aparecida ; Ribeiro-Dias, Fatima ; Machado, Giovanna ; Fessel, Melissa Regina ; Chudzinski-Tavassi, Ana Marisa ; Ronconi, Celia Machado ; Goncalves, Debora ; Curi, Rui ; Oliveira Jr, Osvaldo N. ; Azevedo, Ricardo Bentes

• Document type: Journal article
• Source: Talanta; v. 243, p. 7-pg., 2022-06-01.

Abstract

Mass testing for the diagnosis of COVID-19 has been hampered in many countries owing to the high cost of genetic material detection. This study reports on a low-cost immunoassay for detecting SARS-CoV-2 within 30 min using dynamic light scattering (DLS). The immunosensor comprises 50-nm gold nanoparticles (AuNPs) functionalized with antibodies against SARS-CoV-2 spike glycoprotein, whose bioconjugation was confirmed using transmission electron microscopy (TEM), UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), and surface-enhanced Raman scattering spectroscopy (SERS). The specific binding of the bioconjugates to the spike protein led to an increase in bioconjugate size, with a limit of detection (LOD) 5.29 x 10(3) TCID50/mL (Tissue Culture Infectious Dose). The immunosensor was also proven to be selective upon interaction with influenza viruses once no increase in size was observed after DLS measurement. The strategy proposed here aimed to use antibodies conjugated to AuNPs as a generic platform that can be extended to other detection principles, enabling technologies for low-cost mass testing for COVID-19. (AU)

• FAPESP's process: 18/22214-6 - Towards a convergence of technologies: from sensing and biosensing to information visualization and machine learning for data analysis in clinical diagnosis
• Grantee: Osvaldo Novais de Oliveira Junior
• Support Opportunities: Research Projects - Thematic Grants