Integrated horizontal convective PCR system for clinical diagnostics

Rapid and accurate disease diagnosis in resource-limited settings is critical for optimizing medical resources and controlling epidemic outbreaks. However, developing a point-of-care detection system that is user-friendly, cost-effective, highly accurate, and exhibits strong specificity remains a formidable challenge. Here, we report an integrated horizontal convection PCR system (IHCS) for clinical point-of-care testing, capable of real-time fluorescence detection. IHCS leverages horizontal thermal convection within a capillary to drive sample flow and temperature cycling for nucleic acid amplification, making it suitable for both home use and on-site rapid detection. Capillary action enables swift sample loading, thereby simplifying the overall procedure, and the horizontal thermal convection overcomes the volume limitations inherent in vertical systems. Validation with 130 clinical samples demonstrated that the system successfully detected HBV, SARS-CoV-2, and influenza A virus within 40 min, achieving excellent sensitivity (>96%) and specificity (100%). Overall, the IHCS integrates microfluidics, thermal engineering, and optical sensing and offers a paradigm-shifting solution for point-of-care diagnostics.