Accelerated CRISPR/Cas12a-Based Point-of-Care Diagnostics Through Critical Coupling Distance Control

Area of Science:

• Biotechnology
• Molecular Diagnostics
• Nanotechnology

Background:

• CRISPR/Cas12a diagnostics show promise but face limitations in speed and sensitivity.
• Resource-limited settings require rapid, low-energy pathogen detection methods.

Purpose of the Study:

• To enhance CRISPR/Cas12a diagnostic performance using a novel DNA nanostructure.
• To improve detection speed and sensitivity for pathogen nucleic acids.

Main Methods:

• Designed triblock DNA-mediated spherical nucleic acids (tSNA) as spatially confined reporters.
• Investigated the correlation between coupling distance on tSNA and Cas12a trans-cleavage efficiency.
• Integrated tSNA into lateral-flow strips for point-of-care testing.

Main Results:

• Demonstrated a 'scooting' reaction model on tSNA, increasing trans-cleavage rate 12-fold.
• Achieved a two-orders-of-magnitude higher sensitivity compared to bulk solutions.
• Reduced pathogen nucleic acid detection time to 3 minutes using tSNA lateral-flow strips.

Conclusions:

• tSNA offers precise spatial control over Cas12a activity, enhancing diagnostic performance.
• The tSNA platform advances CRISPR-powered point-of-care (POC) diagnostics for resource-limited environments.
• This 'size-matching' model provides a new strategy for regulating enzymatic activity in diagnostics.