Plasmon-Enhanced Fluorescence Test Strip for Rapid COVID-19 Detection

Infectious diseases, such as COVID-19, caused by the SARS-CoV-2 virus, have had a global impact in recent years. It is crucial to conduct rapid Covid-19 testing early on the onset of disease to effectively manage the spread of SARS-CoV-2 virus and to have medical intervention early. In this study, plasmon-enhanced fluorescence probes have been developed to detect SARS-CoV-2 antigen via lateral flow immunoassay. Surface plasmon resonance (SPR) is utilized to enhance the intensity of fluorescence dyes based on principles of excitation and emission enhancement. Then, a paper microfluidic strip has been engineered with integrated fluorescent probes to generate a point-of-care testing (POCT) tool. The performance of the integrated microfluidic strip has been used to test clinical samples and to compare its sensitivity and specificity with commercial rapid Covid-19 antigen test kits. This study highlights the potential of plasmon-enhanced fluorescence in managing infectious diseases.