便捷式数字化等温扩增微流控芯片

A portable digital isothermal amplification-based microfluidic chip

摘要:

本研究旨在开发一种低成本、便携式且绝对定量的数字核酸检测芯片，以解决现有数字核酸检测方法成本高、样本损失、操作复杂和对设备依赖性强等问题。为此，进行了一种创新的芯片设计：通过流体通道与真空通道的解耦和分离，采用分形结构设计流体通道，实现了样本的高效自动分配和100%的样本利用率；同时，设计的真空通道有效解决了分形结构芯片在预脱气和负压维持方面的难题，无需预先进行耗时的脱气操作，使检测可随时进行。此外，基于黑色聚二甲基硅氧烷(polydimethylsiloxane, PDMS)材料开发的数字重组酶聚合酶扩增(digital recombinase polymerase amplification, dRPA)芯片，展现出优异的光学成像能力和强大的抗背景荧光干扰能力，为光学检测提供了理想平台。本研究还提出了一种新的防蒸发策略，通过水溶液包围每个微室防止试剂蒸发，进一步优化了检测性能。最终，本研究成功开发出一种便携式的dRPA核酸检测解决方案，仅需简单的手动操作和智能手机即可完成检测。该方案不仅保留了简单、低成本、可扩展性和绝对定量的优势，还显著提高了检测的便捷性和实用性，为便携式核酸检测的广泛应用奠定了基础。这种创新的检测方案有望在资源有限的环境中实现快速、准确的核酸检测，推动现场快速诊断技术的发展。

Abstract:

This study aims to develop a low-cost, portable, and quantitative digital nucleic acid detection chip to address the issues of high cost, sample loss, complex operation, and strong equipment dependency associated with existing digital nucleic acid detection methods. To achieve this, an innovative chip design was proposed. The fluidic channels were decoupled and separated from the vacuum channels, and a fractal structure was employed to design the fluidic channels, enabling efficient automatic sample distribution and 100% sample utilization. Meanwhile, the vacuum channels effectively resolved the challenges of pre-degassing and maintaining negative pressure in fractal structure chips, eliminating the need for time-consuming pre-degassing operations, and allowing detection to be performed at any time. Additionally, a digital recombinase polymerase amplification (dRPA) chip based on black polydimethylsiloxane (PDMS) material was developed, which exhibited excellent optical imaging capabilities and strong resistance to background fluorescence interference, providing an ideal platform for optical detection. A novel anti-evaporation strategy was also proposed, where each microchamber was surrounded by an aqueous solution to prevent reagent evaporation, further optimizing detection performance. Ultimately, a portable dRPA nucleic acid detection solution was successfully developed, requiring only simple manual operation and a smartphone to complete the detection. This solution not only retains the advantages of simplicity, low cost, scalability, and absolute quantification but also significantly enhances the convenience and practicality of detection, laying the foundation for the widespread application of portable nucleic acid detection. This innovative detection solution is expected to enable rapid and accurate nucleic acid detection in resource-limited settings and promote the development of on-site rapid diagnostic technologies.