Guangzhou Key Laboratory of Sensing Materials and Devices, Center for Advanced Analytical Science, School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, P. R. China.
Anal Chem. 2022 Jul 19;94(28):10206-10212. doi: 10.1021/acs.analchem.2c01699. Epub 2022 Jul 1.
As a class of oligosaccharide chain-containing proteins, glycoproteins are of great value in screening and early diagnosis of malignant tumors and other major diseases. Herein, we report a universal boronate affinity-based electrochemical aptasensor for point-of-care glycoprotein detection. Aptasensing of glycoproteins involves the specific recognition and capture of target glycoproteins by end-tethered nucleic acid aptamers and the site-specific labeling of ferrocene tags via the phenylboronic acid (PBA)-based boronate affinity interactions because the -diol sites of oligosaccharide chains on glycoproteins can selectively react with the PBA receptor groups to form cyclic phenylborates in aqueous basic media. Due to the presence of hundreds to thousands of -diol sites on a glycoprotein, a large number of ferrocene tags can be recruited for the signal-on aptasensing of glycoproteins at a low-abundance level, eliminating the need for extra amplification strategies. As a result, the boronate affinity-based electrochemical aptasensor is highly sensitive and selective for glycoprotein detection and tolerant to the false-positive results. The detection limit for α-fetoprotein (AFP) is 0.037 ng/mL, with a linear response ranging from 0.1 to 100 ng/mL. In addition to the merits of simple operation, short assay time, and low detection cost, the aptasensor is applicable to the detection of glycoproteins in serum samples and the point-of-care detection using disposable flexible electrodes. Overall, this work provides a universal and promising platform for the point-of-care detection of glycoproteins, holding great potential in screening and early diagnosis of glycoprotein-related malignant tumors and other major diseases.
作为一类含有寡糖链的蛋白质，糖蛋白在恶性肿瘤等重大疾病的筛选和早期诊断中具有重要价值。在此，我们报道了一种基于硼酸亲和的通用电化学生物适体传感器，用于即时检测糖蛋白。糖蛋白的适体传感涉及通过末端连接的核酸适体对靶标糖蛋白的特异性识别和捕获，以及通过基于苯硼酸（PBA）的硼酸亲和相互作用对二茂铁标记物的位点特异性标记，因为糖蛋白上寡糖链的 -二醇位点可以选择性地与 PBA 受体基团反应，在碱性水介质中形成环状苯硼酸酯。由于糖蛋白上存在数百到数千个 -二醇位点，因此可以招募大量的二茂铁标记物，用于低丰度水平的糖蛋白信号开启适体传感，从而无需额外的放大策略。因此，基于硼酸亲和的电化学生物适体传感器对糖蛋白检测具有高度的灵敏度和选择性，并且对假阳性结果具有耐受性。对甲胎蛋白（AFP）的检测限为 0.037ng/mL，线性响应范围为 0.1 至 100ng/mL。除了操作简单、检测时间短、检测成本低等优点外，该适体传感器还适用于血清样品中糖蛋白的检测和使用一次性柔性电极的即时检测。总之，这项工作为即时检测糖蛋白提供了一种通用且有前途的平台，在糖蛋白相关恶性肿瘤等重大疾病的筛选和早期诊断中具有巨大潜力。
