Development of colloidal Gold nanoparticle based lateral-flow assay for rapid detection of SARS-CoV-2 showing enhanced sensitivity and specificity

Abstract

To stop the spread of COVID-19 in this outbreak, diagnostic testing is essential. Quick diagnostic tests must be employed in this pandemic, which is brought on by the severe acute respiratory syndrome (SARS)-CoV-2 virus, to successfully treat and manage COVID-19. There are several problems with the present RT-PCR system that the lateral flow assay (LFA), a kind of clinically sensitive diagnostic test, may be able to fix, especially in low-and middle-income nations. Gold nanoparticle-(AuNP-LFA) is a practical method for detecting COVID-19 in basic hospitals and laboratories, particularly in emergency situations where many samples must be quickly examined. Safe, accurate, and non-toxic diagnostic tests must be employed during the pandemic, to successfully treat and manage COVID-19. Recombinant SARS-CoV-2 nucleocapsid monoclonal antibody was employed to detect COVID-19 antigens in the presence of patients to establish a fast LFA for COVID-19. Synthesis of colloidal gold particles and antibody colloidal gold conjugates was evaluated by using UV/Vis spectroscopy. A capture line made of anti-SARS-CoV-2 antibody was coated on nitrocellulose membrane. To create the control line, goat anti-mouse IgG monoclonal antibody was coated. On a polystyrene backing board, the immunochromatographic strip was constructed in the ideal order. Using ELISA as the standard procedure, the strips’ sensitivity and specificity were assessed. The results’ stability and repeatability were evaluated over a 9-month period. Colloidal gold nanoparticle-based LFAs created in this study can be employed for quicker and more accurate detection of SARS-CoV-2.