Selective counting and sizing of single virus particles using fluorescent aptamer-based nanoparticle tracking...

Area of Science:

• Virology
• Nanotechnology
• Biomedical Diagnostics

Background:

• Current methods for detecting and counting single virus particles are limited to specific sizes and purified samples.
• Broad size distribution and complex sample matrices pose challenges for accurate viral quantification.

Purpose of the Study:

• To develop a calibration-free method for selective recognition, counting, and sizing of virus particles.
• To demonstrate the method's efficacy in detecting human respiratory syncytial virus (RSV) in clinical samples.

Main Methods:

• Selective labeling of RSV attachment glycoproteins (G) with fluorescent aptamers.
• Single-particle identification, sizing, and counting using fluorescent nanoparticle tracking analysis.
• Application to unprocessed throat swab samples.

Main Results:

• Successful detection and quantification of single RSV particles in throat swab samples.
• The method demonstrated a broad size distribution detection capability for RSV.
• Enabled discrimination of viral elements, virus forms, and associations based on selective recognition and sizing.

Conclusions:

• The proposed calibration-free method offers a versatile approach for virus detection and quantification.
• It shows promise for diagnostic applications, particularly for viruses with broad size distributions like RSV.
• The technique allows for detailed characterization of viral particles in complex biological samples.