Digital plasmonic nanobubble detection for rapid and ultrasensitive virus diagnostics

Area of Science:

• Nanotechnology
• Biomedical Diagnostics
• Optofluidics

Background:

• Rapid and sensitive infectious disease diagnostics are crucial, highlighted by the COVID-19 pandemic.
• Current diagnostic methods often require complex steps like separation and amplification.

Purpose of the Study:

• To introduce a novel diagnostic strategy, DIgitAl plasMONic nanobubble Detection (DIAMOND), for rapid and ultrasensitive detection of infectious diseases.
• To demonstrate DIAMOND's capability for compartment-free digital counting and homogeneous immunoassays.

Main Methods:

• Utilizing plasmonic nanobubbles generated by laser-heated gold nanoparticles (NPs) for single-NP detection.
• Employing an optofluidic setup for compartment-free digital counting in homogeneous immunoassays.
• Applying the DIAMOND strategy to detect respiratory syncytial virus (RSV) in nasal swab samples.

Main Results:

• DIAMOND achieved a detection limit of approximately 100 PFU/mL (1 RNA copy/µL) for RSV.
• The method demonstrated compartment-free digital counting without separation or amplification steps.
• Successful specific detection of RSV spiked in nasal swab samples was achieved.

Conclusions:

• DIAMOND is a one-step, single-NP detection platform for direct sensing of intact viruses at room temperature.
• The technology offers advantages such as no complex liquid handling, making it suitable for rapid and ultrasensitive diagnostics.
• DIAMOND presents a promising platform technology for addressing the unmet need for efficient infectious disease diagnostics.