Label-free and amplification-free viral RNA quantification from primate biofluids using a trapping-assisted...

Area of Science:

• Biomolecular Engineering
• Nanotechnology
• Molecular Diagnostics

Background:

• Current viral diagnostic tools like PCR and antigen tests have limitations in performance, sample versatility, or complexity.
• There is a critical need for advanced diagnostic solutions capable of high-performance, versatile, point-of-use viral detection.

Purpose of the Study:

• To develop and validate a label-free, amplification-free nanopore sensor platform for direct viral RNA detection and quantification.
• To demonstrate the platform's capability across various biological fluids and viral targets, including Zika and SARS-CoV-2.

Main Methods:

• Utilized an optofluidic chip integrating optical waveguides, a fluidic channel, and a solid-state nanopore for biomolecule sensing.
• Employed microbead capture, optical trapping, and target release for enhanced RNA concentration at the nanopore.
• Performed longitudinal studies on Zika and SARS-CoV-2 in animal models, analyzing various clinical sample types.

Main Results:

• Achieved amplification-free RNA quantification across clinically relevant ranges, even surpassing RT-qPCR limits in some cases.
• Demonstrated broad biofluid compatibility, including semen, urine, whole blood, swabs, and bronchoalveolar lavage.
• The sensor platform showed high specificity and a low limit of detection, enabling direct viral RNA detection.

Conclusions:

• The developed nanopore sensor platform offers a versatile, high-performance, and simple approach to molecular diagnostics.
• This amplification-free assay shows significant potential for point-of-care diagnostics of viral nucleic acids and other biomolecules.
• The technology's potential for microfluidic integration suggests a transformative impact on molecular diagnostics.