The enzyme-linked immunosorbent assay (ELISA) is one of the most commonly implemented clinical diagnostic tools for the detection and quantification of protein biomarkers. However, conventional ELISA tests require sophisticated infrastructure, expensive reagents, long assay time, and expertise for operation, which are not often easily accessible in resource-limited settings. Microfluidic ELISA-chip based point-of-care (POC) testing allows miniaturization and integration of complex functions that facilitate their usage in limited-resource settings. The current work demonstrates a simple, portable, low cost and equipment-free paper/poly(methyl methacrylate) (PMMA) integrated microfluidic ELISA-chip as a POC device with a visual distance-based readout for quantitative detection of clinical biomarkers. The integrated paper/PMMA ELISA-chip utilizes the movement of immunoassay complexes with magnetic beads by a permanent magnet in a PMMA part of the compartment. The target concentration is translated into a visual distance signal readout for quantitative detection of biomarkers in a μPAD. Because it does not require sophisticated instruments and has the added advantages of low cost, easy operation, and disposability with quantitative visual readout, the paper/PMMA ELISA-chip holds great promise for portable detection of target bioanalytes as a POC diagnostic tool in resource-limited setups.

中文翻译：

---

基于距离的纸/ PMMA集成ELISA芯片，用于定量检测免疫球蛋白G。

酶联免疫吸附测定（ELISA）是检测和定量蛋白质生物标记物最常用的临床诊断工具之一。但是，常规ELISA测试需要复杂的基础设施，昂贵的试剂，较长的测定时间和操作专业知识，而在资源有限的环境中通常不容易获得这些测试。基于微流体ELISA芯片的即时检验（POC）测试可实现复杂功能的小型化和集成，从而简化其在有限资源设置中的使用。当前的工作展示了一种简单，便携式，低成本，无需设备的纸/聚（甲基丙烯酸甲酯）（PMMA）集成微流ELISA芯片，作为POC设备，具有基于视觉距离的读数，可以定量检测临床生物标志物。集成的纸张/ PMMA ELISA芯片利用隔室PMMA部分中的永磁体移动带有磁珠的免疫分析复合物。将目标浓度转换为可见距离信号读数，以定量检测μPAD中的生物标志物。由于它不需要复杂的仪器，并且具有低成本，易于操作以及具有定量视觉读数的可处置性等优点，因此纸/ PMMA ELISA芯片具有可移植性检测目标生物分析物的广阔前景，可作为资源中的POC诊断工具。有限的设置。