A low-cost bifunctional immunochromatographic colorimetric biosensor was developed that can be read visually or by using an optical density scanner. Five test lines (T lines) coated with different antigens were set on a nitrocellulose (NC) membrane to indicate the concentration of analyte. This method was applied for the detection of dexamethasone. The corresponding detection range was 0.1–9 ng mL−1, and the detection limit for dexamethasone in food supplements and cosmetic samples was 2.0 μg kg−1. For visual inspection of the colour the quantitative relative error range between the proposed method and liquid chromatography was −62 to −25%, with a detection time of only 10 min. More accurate assay results were obtained by using an optical density scanner with the relative error range of −31 to 20%. The results indicated that the proposed method has the potential of application for rapid and efficient screening of dexamethasone in cosmetics and food supplements. Graphical abstract Graphical abstract

中文翻译：

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基于上转换荧光纳米粒子的半定量免疫层析比色生物传感器检测地塞米松

开发了一种低成本的双功能免疫色谱比色生物传感器，可以通过视觉或使用光密度扫描仪读取。用不同抗原包被的五个测试线（T 线）设置在硝酸纤维素 (NC) 膜上以指示分析物的浓度。该方法用于地塞米松的检测。相应的检测范围为 0.1–9 ng mL-1，食品补充剂和化妆品样品中地塞米松的检测限为 2.0 μg kg-1。对于颜色的视觉检查，所提出的方法和液相色谱之间的定量相对误差范围为 -62% 至 -25%，检测时间仅为 10 分钟。通过使用相对误差范围为 -31 至 20% 的光密度扫描仪获得了更准确的测定结果。结果表明，所提出的方法具有用于快速有效筛选化妆品和食品补充剂中地塞米松的潜力。图形摘要图形摘要