We report a method for converting the colorimetric results of an enzyme-linked immunosorbent assay (ELISA) into length based on the coffee-ring effect, so that the quantitative detection of analytes can be carried out simply using a ruler. The influence of the shape and lamination of the paper strip on the test results is studied. As a demonstration, human IgG is quantitatively analyzed. It is found that the width of the colored stains correlates with the concentration of the analyte which can be measured for quantitative analysis. The method is promising for quantitative point-of-care detection of biomarkers under resource-limited settings.

中文翻译：

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使用咖啡尺效应将颜色转换为长度，以便使用直尺作为读数进行定量免疫分析†

我们报告了一种基于咖啡环效应将酶联免疫吸附测定（ELISA）的比色结果转换为长度的方法，以便可以使用标尺简单地进行分析物的定量检测。研究了纸带的形状和层压对测试结果的影响。作为演示，对人IgG进行了定量分析。已经发现，有色污渍的宽度与可以被测量用于定量分析的分析物的浓度相关。该方法有望在资源有限的环境下定量检测生物标志物的即时护理。