Sun Jihong, Duan Sixuan, Xu Weiqin, He Wenjun, Li Tong, Liu Sanli, Hoettges Kai, Zhu Junhui, Leach Mark, Song Pengfei
School of Advanced Technology, Xi'an Jiaotong-Liverpool University, 111 Ren'ai Road, Suzhou, 215000, China; Department of Electrical and Electronic Engineering, University of Liverpool, Foundation Building, Brownlow Hill, Liverpool, L69 7ZX, UK; State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, No. 74, Yanta West Road, Xi'an, 710054, China.
School of Advanced Technology, Xi'an Jiaotong-Liverpool University, 111 Ren'ai Road, Suzhou, 215000, China; Department of Electrical and Electronic Engineering, University of Liverpool, Foundation Building, Brownlow Hill, Liverpool, L69 7ZX, UK.
Anal Chim Acta. 2025 Jul 8;1358:344013. doi: 10.1016/j.aca.2025.344013. Epub 2025 Apr 10.
In recent years, adapting immunoassay technologies for point-of-care testing (POCT) to enable low-cost, on-site diagnostics has gained great attention. Among the various approaches to achieving this goal, microfluidic paper-based analytical devices (μPADs) have emerged as a promising platform. These devices are particularly appealing due to their low cost, simple procedures, and minimal sample consumption. Among the detection methods used in μPADs, chemiluminescence (CL) has attracted widespread attention for its high sensitivity. However, existing CL immunoassays often require expensive detection equipment and extensive manual operation, which limits their use in resource-poor areas or where trained personnel are lacking.
In this study, we developed a newly designed μPAD for CL immunoassays, leveraging smartphone-based image capture, valve-regulated reaction process, and app-driven result analysis to enable fully automated detection. Each element of the device was highly integrated and designed for programmable operation, enhancing reliability and stability. An app was developed to manage the entire process, maximizing the convenience of smartphones. The device's effectiveness was calibrated using rabbit IgG as a model, achieving a limit of detection (LOD) of 62.4 pg/mL, which represents an improvement compared to the colorimetric ELISA method with a LOD of 3 ng/mL (20pM). We then applied the device to detect tau protein, a biomarker associated with Alzheimer's disease and achieved a detection limit of 26.1 pg/mL, which is lower than the clinical cut-off value.
Our device achieves complete automation and integrates the versatility of μPADs with the precision of CL immunoassays, offering an effective and accessible solution for POCT. By incorporating a user-friendly smartphone interface, it simplifies operation while maintain detection sensitivity, providing a practical and valuable improvement in the development of POCT technologies.
近年来，使免疫分析技术适用于即时检测（POCT）以实现低成本的现场诊断受到了广泛关注。在实现这一目标的各种方法中，微流控纸基分析装置（μPADs）已成为一个有前景的平台。这些装置因其低成本、操作简单和样品消耗少而特别具有吸引力。在μPADs中使用的检测方法中，化学发光（CL）因其高灵敏度而受到广泛关注。然而，现有的CL免疫分析通常需要昂贵的检测设备和大量的人工操作，这限制了它们在资源匮乏地区或缺乏训练有素人员的地方的使用。
在本研究中，我们开发了一种新设计的用于CL免疫分析的μPAD，利用基于智能手机的图像捕获、阀控反应过程和应用程序驱动的结果分析来实现全自动检测。该装置的每个元件都高度集成，并设计用于可编程操作，提高了可靠性和稳定性。开发了一个应用程序来管理整个过程，最大限度地发挥了智能手机的便利性。以兔IgG为模型对该装置的有效性进行了校准，检测限（LOD）达到62.4 pg/mL，与比色ELISA方法的LOD为3 ng/mL（20 pM）相比有所提高。然后，我们将该装置应用于检测与阿尔茨海默病相关的生物标志物tau蛋白，检测限达到26.1 pg/mL，低于临床临界值。
我们的装置实现了完全自动化，并将μPADs的多功能性与CL免疫分析的精度相结合，为POCT提供了一种有效且易于使用的解决方案。通过纳入用户友好的智能手机界面，它简化了操作同时保持检测灵敏度，为POCT技术的发展提供了切实且有价值的改进。
