Proximity‐Unlocked Luminescence by Sequential Enzymatic Reactions from Antibody and Antibody/Aptamer (PULSERAA): A Platform for Detection and Visualization of Virus‐Containing Spots

The SARS‐CoV‐2 pandemic has challenged more scientists to detect viruses and to visualize virus‐containing spots for diagnosis and infection control; however, detection principles of commercially available technologies are not optimal for visualization. Here, a convenient and universal homogeneous detection platform named proximity‐unlocked luminescence by sequential enzymatic reactions from antibody and antibody/aptamer (PULSERAA) is developed. This is designed so that the signal appears only when the donor and acceptor are in proximity on the viral surface. PULSERAA specifically detected in the range of 25–500 digital copies/mL of inactivated SARS‐CoV‐2 after simply mixing reagents; it is elucidated that the accumulation of chemical species in a limited space of the viral surface contributed to such high sensitivity. PULSERAA was quickly adapated to detect another virus variant, inactivated influenza A virus, and infectious SARS‐CoV‐2 in a clinical sample. Furthermore, on‐site (direct, rapid, and portable) visualization of the inactivated SARS‐CoV‐2‐containing spots by a conventional smartphone camera was achieved, demonstrating that PULSERAA can be a practical tool for preventing the next pandemic in the future. A homogeneous immunoassay named proximity‐unlocked luminescence by sequential enzymatic reactions from antibody and antibody/aptamer (PULSERAA) is developed, which enabled not only rapid virus detection in 15 min with high sensitivity and specificity but also the on‐site visualization of the virus‐containing spots on a surface through a smartphone camera after spraying reagents.