Rotary Piston Valve with Surface-Engraved Microfluidic Channels for Cassette-Based Nucleic Acid Detection

Abstract Point-of-care testing (POCT) plays a crucial role in both clinical- and home-based diagnostics. Integrated POCT systems that combine nucleic acid extraction with detection provide significant advantages, including portable operation, rapid processing, and high sensitivity. In this work, we present a fully automated and integrated nucleic acid detection system based on microfluidic chips with a surface-engraved rotary piston (SERP), which incorporates all of the liquid channels on the surface of one valve. This design consists of only three parts: the chip, the rubber sealing ring, and the rotary valve containing microfluidic channels, allowing the sequential connection of reaction chambers to facilitate nucleic acid extraction, recombinase polymerase amplification (RPA), and clustered regularly interspaced short palindromic repeats (CRISPR) into a single chip. Our chip consists of only three components, can be fabricated directly by 3D printing, and features a simple structure with a compact size. This platform was employed for the detection of human papillomavirus (HPV16) DNA, achieving a limit of detection (LOD) as low as 60 copies/mL. This result underscores the potential of the SERP as a rapid, cost-effective, and modular solution for POCT applications.