This study introduces a fluorescent immunosensor colour panel with antibody-conjugated quantum dots for detecting CA19-9 in human serum. The immunosensors presented decreasing fluorescence with increasing CA19-9 concentrations, with a linear detection range from 0.01 to 501.87 U mL−1 and detection limits of 1.66 × 10⁻⁴, 2.71 × 10⁻⁴, and 5.45 × 10⁻⁴ U mL−1 for the green-, orange-, and red-emitting conjugates in human serum. These limits are well below the 37 U mL−1 cutoff for early pancreatic cancer risk. The immunosensor panel is simple, sensitive, and specific, offering a visual colour readout for rapid CA19-9 detection, making it ideal for point-of-care applications. The results highlight the potential of the developed conjugates as a sensitive fluorescence colour panel for detecting CA19-9 across a wide range in human serum, both below and above the pancreatic cancer cutoff. With just 200 μL of sample and a single pre-filtration step, the assay delivers results in under 15 min, offering a cost-effective and efficient platform for point-of-care use.

中文翻译：

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使用量子点抗体偶联物的光学免疫传感器检测板用于高灵敏度检测碳水化合物抗原 19-9 （CA19-9）


本研究介绍了一种带有抗体偶联量子点的荧光免疫传感器彩色面板，用于检测人血清中的 CA19-9。免疫传感器随着 CA19-9 浓度的增加而呈现荧光减弱，线性检测范围为 0.01 至 501.87 U mL-1，检测限为 1.66 × 10⁻⁴、2.71 × 10⁻⁴ 和 5.45 × 10⁻⁴ U mL-1 人血清中绿色、橙色和红色发射偶联物。这些限值远低于早期胰腺癌风险的 37 U mL-1 临界值。免疫传感器检测组合简单、灵敏且具有特异性，为快速检测 CA19-9 提供视觉颜色读数，使其成为即时应用的理想选择。结果突出了开发的偶联物作为灵敏荧光彩色面板的潜力，可在人血清中的广泛范围内检测 CA19-9，包括低于和高于胰腺癌临界值。该分析仅需 200 μL 样品和单个预过滤步骤，可在 15 分钟内提供结果，为即时护理提供了一个经济高效的平台。