A paper-based fluorescent biosensing platform for miRNA detection with dual high-throughput and smartphone readout

Area of Science:

• Biomedical Engineering
• Molecular Diagnostics
• Nanotechnology

Background:

• MicroRNA (miRNA) detection is crucial for liquid biopsy diagnostics.
• Current methods (qRT-PCR, microarrays) are complex and not point-of-care friendly.
• There is a need for rapid, accessible miRNA detection platforms.

Purpose of the Study:

• To develop a flexible, dry-reagent paper-based biosensing platform for quantitative miRNA detection.
• To enable rapid and portable miRNA analysis.
• To establish a foundation for point-of-care nucleic acid testing.

Main Methods:

• Utilized fluorescent molecular beacon (MB)-functionalised gold nanoparticles (AuNPs) embedded in nitrocellulose membranes.
• Developed a paper-based assay for target-induced miRNA hybridization and fluorescence signal generation.
• Enabled quantification using microplate readers or a portable smartphone-based optical reader.

Main Results:

• Achieved robust miRNA detection in the low-nanomolar range directly on paper.
• Demonstrated improved apparent affinity compared to solution-based measurements.
• The platform is compatible with amplification strategies for enhanced sensitivity.

Conclusions:

• The developed platform is user-friendly, adaptable, and suitable for decentralized testing.
• It shows potential for point-of-care nucleic acid testing in clinical and resource-limited settings.
• Further sensitivity improvements are needed for direct clinical liquid biopsy analysis without amplification.