Li Shengqiang, Liu Xu, Liu Shenglin, Guo Mei, Liu Cuiying, Pei Ming
Clinical Laboratory, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, 300000, China.
Clinical Laboratory, Tianjin Xi Qing Hospital Tianjin, 300000, China.
Anal Chim Acta. 2021 Jan 2;1141:21-27. doi: 10.1016/j.aca.2020.10.030. Epub 2020 Oct 19.
At present, alpha fetoprotein (AFP) is mainly used as a serum marker of primary Hepatocellular carcinoma. A simple, enzyme-free sensing strategy is introduced for highly sensitive fluorescence detection of AFP. This detection strategy is based on aptamer recognition and mismatched catalytic hairpin assembly (MCHA). At first, Trigger is locked by aptamer before the introduction of AFP in this aptamer-MCHA system. The aptamer preferentially combines with AFP via powerful attraction in the presence of AFP. This results in the release of trigger and initiation of MCHA cycle, thus forming the H1 and H2 double chain complexes (denoted as H1@H2). Finally, H1@H2 and double chain structure containing fluorophore and its quenched group- BHQ1 (denoted as F@Q) initiated displacement reaction, which caused double chain separation and fluorescence recovery. This assay produces a wide detection range, which is from 0.1 ng mL to 10 μg mL and the limit of detection as 0.033 ng mL. The whole detection process was performed at 37 °C for 60 min. In addition, this assay had high anti-interference ability and could be used to detect AFP in clinical serum. This novel AFP detection strategy is able to screen of Hepatocellular carcinoma.
目前，甲胎蛋白（AFP）主要用作原发性肝细胞癌的血清标志物。本文介绍了一种简单的无酶传感策略，用于高灵敏度荧光检测AFP。该检测策略基于适体识别和错配催化发夹组装（MCHA）。首先，在该适体-MCHA系统中引入AFP之前，触发链被适体锁定。在AFP存在的情况下，适体通过强大的吸引力优先与AFP结合。这导致触发链释放并启动MCHA循环，从而形成H1和H2双链复合物（表示为H1@H2）。最后，H1@H2与含有荧光团及其猝灭基团BHQ1的双链结构（表示为F@Q）引发置换反应，导致双链分离并荧光恢复。该检测方法具有较宽的检测范围，为0.1 ng/mL至10 μg/mL，检测限为0.033 ng/mL。整个检测过程在37℃下进行60分钟。此外，该检测方法具有高抗干扰能力，可用于检测临床血清中的AFP。这种新型的AFP检测策略能够筛查肝细胞癌。
