Lin Xiaojuan, Li Shengqiang, Zhang Bogang, Yang Hua, Zhang Kai, Huang Hongge
Department of Clinical Laboratory, The Third Hospital of Xingtai, Xingtai, Hebei 054100, China.
Anal Methods. 2020 Dec 7;12(45):5496-5502. doi: 10.1039/d0ay01326a. Epub 2020 Nov 5.
Carcinoembryonic antigen (CEA) is a disease biomarker, which can reflect the existence of tumors. The accurate detection of CEA in clinical samples is highly valuable for diagnosis of tumors. Herein, we developed an enzyme-free fluorescent biosensor for highly sensitive detection of CEA based on an aptamer-induced entropy-driven circuit. The aptamer hairpin specifically bound to CEA to expose the locked domain. Then, the exposed domain could trigger disassembly of multiple fluorophore strands from the three-strand complexes with the aid of fuel strands, leading to the production of remarkable amplified fluorescent signals. The one-step and homogeneous method exhibited high specificity and a wide linear range from 10 pg mL to 500 ng mL with a low limit of detection of 4.2 pg mL. What's more, the whole detection process could be performed within 45 min and did not involve the use of any protein enzymes and antibodies. The developed strategy could also be applied to detect CEA in clinical samples with satisfactory results. Therefore, the strategy is an alternative sensing method for the detection of CEA.
癌胚抗原（CEA）是一种疾病生物标志物，可反映肿瘤的存在。在临床样本中准确检测CEA对肿瘤诊断具有重要价值。在此，我们基于适体诱导的熵驱动电路开发了一种用于高灵敏度检测CEA的无酶荧光生物传感器。适体发夹特异性结合CEA以暴露锁定结构域。然后，暴露的结构域可借助燃料链触发多荧光团链从三链复合物中解离，导致产生显著放大的荧光信号。这种一步法且均相的方法具有高特异性，线性范围宽，从10 pg/mL到500 ng/mL，检测限低至4.2 pg/mL。此外，整个检测过程可在45分钟内完成，且不涉及任何蛋白酶和抗体的使用。所开发的策略也可应用于临床样本中CEA的检测，结果令人满意。因此，该策略是检测CEA的一种替代传感方法。
