College of Life Sciences, China Jiliang University, Hangzhou 310018, China.
Center for Advanced Measurement Science, National Institute of Metrology, Beijing 100029, China.
Int J Mol Sci. 2022 Sep 1;23(17):9991. doi: 10.3390/ijms23179991.
Carbohydrate antigen 199 (CA199) is a serum biomarker which has certain value and significance in the diagnosis, prognosis, treatment, and postoperative monitoring of cancer. In this study, a lateral flow immunoassay based on europium (III) polystyrene time-resolved fluorescence microspheres (TRFM-based LFIA), integrated with a portable fluorescence reader, has been successfully establish for rapid and quantitative analysis of CA199 in human serum. Briefly, time-resolved fluorescence microspheres (TRFMs) were conjugated with antibody I (Ab1) against CA199 as detection probes, and antibody II (Ab2) was coated as capture element, and a "TRFMs-Ab1-CA199-Ab2" sandwich format would form when CA199 was detected by the TRFM-based LFIA. Under the optimal parameters, the detection limit of the TRFM-based LFIA for visible quantitation with the help of an ultraviolet light was 4.125 U/mL, which was four times lower than that of LFIA based on gold nanoparticles. Additionally, the fluorescence ratio is well linearly correlated with the CA199 concentration (0.00-66.0 U/mL) and logarithmic concentration (66.0-264.0 U/mL) for quantitative detection. Serum samples from 10 healthy people and 10 liver cancer patients were tested to confirm the performances of the point-of-care application of the TRFM-based LFIA, 20.0 U/mL of CA199 in human serum was defined as the threshold for distinguishing healthy people from liver cancer patients with an accuracy of about 60%. The establishment of TRFM-based LFIA will provide a sensitive, convenient, and efficient technical support for rapid screening of CA199 in cancer diagnosis and prognosis.
糖类抗原 199（CA199）是一种血清生物标志物，在癌症的诊断、预后、治疗和术后监测中具有一定的价值和意义。在这项研究中，我们成功地建立了一种基于铕（III）聚苯乙烯时间分辨荧光微球（基于 TRFM 的 LFIA）的侧向流动免疫分析方法，该方法与便携式荧光阅读器集成在一起，可用于快速定量分析人血清中的 CA199。简要地说，时间分辨荧光微球（TRFMs）与针对 CA199 的抗体 I（Ab1）偶联作为检测探针，并且抗体 II（Ab2）作为捕获元件被涂覆，当 CA199 通过基于 TRFM 的 LFIA 进行检测时，会形成“TRFMs-Ab1-CA199-Ab2”三明治结构。在最佳参数下，基于 TRFM 的 LFIA 在紫外光的帮助下进行可见定量的检测限为 4.125 U/mL，比基于金纳米粒子的 LFIA 低四倍。此外，荧光比与 CA199 浓度（0.00-66.0 U/mL）和对数浓度（66.0-264.0 U/mL）的定量检测呈良好的线性相关。为了确认基于 TRFM 的 LFIA 的即时护理应用的性能，我们测试了来自 10 名健康人和 10 名肝癌患者的血清样本，以 20.0 U/mL 的 CA199 作为区分健康人和肝癌患者的阈值，准确率约为 60%。基于 TRFM 的 LFIA 的建立将为癌症诊断和预后中 CA199 的快速筛选提供灵敏、方便和高效的技术支持。
