Plasmonic real-time polymerase chain reaction system for point-of-care diagnostics

Abstract

Rapid and accurate identification of virus at point-of-care level play a vital role in preventing fast spread of contagious viral disease. Real-time reverse transcription polymerase chain reaction (PCR) are utilized as gold standard for highly sensitive and selective assay in amplifying and quantifying target genomic sequence. However, real-time PCR has limitations for point-ofcare diagnostics such as expensive and bulky equipment with slow and difficult process. Although rapid gene amplification methods using fast thermal cycler have been sufficiently studied, it is still not suitable for point-of-care diagnostics. In this study, we report handheld plasmonic real-time PCR system for ultrafast point-of-care molecular diagnostics. Nanoplasmonic substrate with high light-to-heat conversion efficiency was microfabricated to combine glass nanopillar arrays with gold nanoislands and platinum thin film resistance temperature detector, and ultrafast photothermal cycling was performed from a white light-emitting diode. PCR cartridge was manufactured by integrating aluminum thin film with plastic chip for high thermal conductivity and light reflectivity. Ultrathin microlens array fluorescence microscope was used for real-time fluorescence imaging in handheld device. The amplification and quantification of coronavirus was clinically demonstrated using the plasmonic real-time PCR system within 10 min. This diagnostic platform enables point-of-care real-time PCR testing in quarantine sites such as multi-use facilities and local hospitals.