Colorimetric Detection of SARS-CoV-2 Using Plasmonic Biosensors and Smartphones

• DOI: 10.1021/acsami.2c15407
• Publication Date: 2022-12-01T15:18:06Z
• Authors: Elsa M. Materón; Faustino R. Gómez; Mariana B. Almeida; Flavio M. Shimizu; Ademar Wong; Kelcilene B. R. T...; Filipe S. R. Silva; Manoel J. A. Lima; Monara Kaelle S. ...; Matias E. Melendez; Nelson Porras; Pedro M. Vieira; Daniel S. Correa; Emanuel Carrilho; Osvaldo N. Oliveira; Ricardo B. Azevedo; Débora Goncalves
• Keywords: Naked eye

Low-cost, instrument-free colorimetric tests were developed to detect SARS-CoV-2 using plasmonic biosensors with Au nanoparticles functionalized polyclonal antibodies (f-AuNPs). Intense color changes noted the naked eye owing plasmon coupling when f-AuNPs form clusters on virus, high sensitivity and a detection limit of 0.28 PFU mL-1 (PFU stands for plaque-forming units) in human saliva. Plasmon was corroborated computer simulations finite-difference time-domain (FDTD) method. The strategies based preparing are robust permit via dynamic light scattering UV-vis spectroscopy without interference from other viruses, such as influenza dengue viruses. diagnosis made smartphone app after processing images collected camera, measuring concentration SARS-CoV-2. Both image machine learning algorithms found provide COVID-19 100% accuracy saliva samples. In subsidiary experiments, we observed that biosensor could be used virus river waters pretreatment. With fast responses requiring small sample amounts (only 20 μL), these can deployed any location within point-of-care paradigm epidemiological control.