Rapid point-of-care nucleic acid detection without purification or amplification

Overview

This technology offers a rapid, amplification-free approach to nucleic acid detection at the point of care. By combining isotachophoresis (ITP)—an electric-field-driven separation technique—with functionalised capture hydrogels, the platform can isolate, pre-concentrate, and detect target DNA or RNA sequences directly from complex biological samples. The approach addresses critical bottlenecks in conventional molecular diagnostics, which rely on multi-step sample purification and nucleic acid amplification (such as PCR), both of which add time, cost, and infrastructure requirements.

The intended applications span clinical diagnostics, infectious disease screening, and field-deployable testing where laboratory infrastructure is unavailable. By removing the need for amplification and laboratory-based sample preparation, the technology has the potential to deliver results in minutes rather than hours, at a fraction of the per-test cost.

Technical specifications

Core mechanism:

• Isotachophoresis purifies and pre-concentrates nucleic acids from crude samples within a microfluidic channel
• Capture hydrogels embedded in the channel selectively bind target nucleic acids via tethered capture strands
• A photolabile linker releases labelled nucleic acids upon UV exposure, allowing transfer to a second capture region for sequence-specific detection
• An integrated heater enables denaturation of double-stranded targets and allows SNP discrimination through melt-curve analysis

Performance targets based on prior validation:

• Pre-concentration factor of up to 10^8-fold through combined ITP and hydrogel capture
• Sample-to-result time in the order of tens of minutes
• Miniaturised, low-cost injection-moulded microfluidic device format
• Smartphone-based instrument control and power management, including integrated UV LED, fluorescence excitation LED, and photodetector

Technology readiness level

The underlying components—ITP-based nucleic acid purification, ITP pre-concentration, hydrogel-based biomarker capture, and miniaturised ITP device fabrication—have each been demonstrated individually in prior published work. The proposed validation plan focuses on integrating these elements into a single microfluidic device with smartphone-controlled instrumentation. Key development steps include building and testing the integrated ITP-hydrogel microfluidic chip, validating the photolabile release and second-capture detection scheme, and demonstrating SNP discrimination via controlled melting. The platform is currently at a mid-stage proof-of-concept level, with ongoing work aimed at producing a fully integrated, field-deployable prototype.