Nanoplasmonic real-time RT-RPA and CRISPR/Cas12a detection for rapid point-of-care molecular diagnostics.

The rapid and precise detection of nucleic acids is crucial for effective disease diagnosis and management at the point-of-care (POC) level. Here we report a palm-sized plasmonic photothermal platform for real-time on-chip recombinase polymerase amplification (RPA) and CRISPR/Cas12a detection. An ultrathin photothermal nanoplasmonic cavity (PNC) of Au nanoislands (AuNIs) and an aluminum reflector delivers uniform and efficient photothermal heating under white LED illumination. The configuration drives isothermal amplification and CRISPR-mediated cleavage in a single microchamber while a fluorescence microlens array (FMLA) camera records real-time emission. The compact platform detects the SARS-CoV-2 E gene in 25 min at 25.7 copies per cartridge and achieves 100 % concordance with RT-qPCR across 42 clinical samples. This all-in-one platform can offer a robust and cost-effective solution for molecular diagnostics, facilitating scalable and real-time testing of infectious diseases in decentralized POC settings.