Digital plasmonic nanobubble detection for rapid and ultrasensitive virus diagnostics

• Published in: Nature communications Vol. 13; no. 1; pp. 1687 - 11
• Main Authors: Liu, Yaning, Ye, Haihang, Huynh, HoangDinh, Xie, Chen, Kang, Peiyuan, Kahn, Jeffrey S., Qin, Zhenpeng
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 30.03.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 639/925/350/59; 692/699/255/2514; 692/700/139; 96/10; Amplification; COVID-19; COVID-19 - diagnosis; Diamonds; DNA Viruses; Gold; Humanities and Social Sciences; Humans; Immunoassay; Immunoassays; Infectious diseases; Laser beam heating; Lasers; multidisciplinary; Nanoparticles; Pandemics; Plasmonics; Public health; Respiratory syncytial virus; Room temperature; Science; Science (multidisciplinary); Viruses
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-29025-w

Rapid and sensitive diagnostics of infectious diseases is an urgent and unmet need as evidenced by the COVID-19 pandemic. Here, we report a strategy, based on DIgitAl plasMONic nanobubble Detection (DIAMOND), to address this need. Plasmonic nanobubbles are transient vapor bubbles generated by laser heating of plasmonic nanoparticles (NPs) and allow single-NP detection. Using gold NPs as labels and an optofluidic setup, we demonstrate that DIAMOND achieves compartment-free digital counting and works on homogeneous immunoassays without separation and amplification steps. DIAMOND allows specific detection of respiratory syncytial virus spiked in nasal swab samples and achieves a detection limit of ~100 PFU/mL (equivalent to 1 RNA copy/µL), which is competitive with digital isothermal amplification for virus detection. Therefore, DIAMOND has the advantages including one-step and single-NP detection, direct sensing of intact viruses at room temperature, and no complex liquid handling, and is a platform technology for rapid and ultrasensitive diagnostics. Digital immunoassays are powerful platforms but are complex and require multiple steps to perform. Here the authors show that digital plasmonic nanobubble detection allows rapid and ultrasensitive diagnostics via a one-step homogeneous immunoassay.