Shanghai Engineering Research Center of Food Rapid Detection, School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
Molecules. 2022 Dec 26;28(1):196. doi: 10.3390/molecules28010196.
Lead contamination in aquatic products is one of the main hazard factors. The aptasensor is a promising detection method for lead ion (Pb(II)) because of its selectivity, but it is easily affected by pH. The combination of ion-imprinted polymers(IIP) with aptamers may improve their stability in different pH conditions. This paper developed a novel electrochemical biosensor for Pb(II) detection by using aptamer-imprinted polymer as a recognition element. The glassy carbon electrode was modified with gold nanoparticles and aptamers. After the aptamer was induced by Pb(II) to form a G-quadruplex conformation, a chitosan-graphene oxide was electrodeposited and cross-linked with glutaraldehyde to form an imprint layer, improving the stability of the biosensor. Under the optimal experimental conditions, the current signal change (∆I) showed a linear correlation of the content of Pb(II) in the range of 0.1-2.0 μg/mL with a detection limit of 0.0796 μg/mL (S/N = 3). The biosensor also exhibited high selectivity for the determination of Pb(II) in the presence of other interfering metal ion. At the same time, the stability of the imprinted layer made the sensor applicable to the detection environment with a pH of 6.4-8.0. Moreover, the sensor was successfully applied to the detection of Pb(II) in mantis shrimp.
水产品中铅污染是主要的危害因素之一。适体传感器由于其选择性，是一种很有前途的铅离子（Pb(II)）检测方法，但它很容易受到 pH 值的影响。将离子印迹聚合物（IIP）与适体结合可以提高它们在不同 pH 条件下的稳定性。本文开发了一种基于适体印迹聚合物作为识别元件的新型电化学生物传感器用于检测 Pb(II)。玻碳电极用纳米金和适体进行修饰。当适体被 Pb(II)诱导形成 G-四链体构象后，用壳聚糖-氧化石墨烯通过电沉积和戊二醛交联形成印迹层，提高了生物传感器的稳定性。在最佳实验条件下，电流信号变化（∆I）与 0.1-2.0μg/mL 范围内 Pb(II)的含量呈线性相关，检测限为 0.0796μg/mL（S/N = 3）。该生物传感器在存在其他干扰金属离子的情况下，对 Pb(II)的测定也表现出较高的选择性。同时，印迹层的稳定性使传感器适用于 pH 值为 6.4-8.0 的检测环境。此外，该传感器成功应用于对螳螂虾中 Pb(II)的检测。
