Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science, MOE, Shandong Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, 266042, PR China.
Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science, MOE, Shandong Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, 266042, PR China.
Anal Chim Acta. 2022 May 22;1208:339841. doi: 10.1016/j.aca.2022.339841. Epub 2022 Apr 16.
Herein, an antifouling electrochemical biosensor based on designed multifunctional peptides with two recognizing branches specific for one target was proposed to improve the target recognition efficiency and sensitivity. The designed multifunctional peptide contains two different recognizing branches (with sequences FYWHCLDE and FYCHTIDE) for immunoglobulin G (IgG), an antifouling sequence (EKEKEK) and an anchoring sequence (CPPPP), which can be immobilized onto the gold nanoparticles (AuNPs) and poly(3,4-ethylenedioxythiophene) (PEDOT) modified electrode surface. Owing to the synergistic effect of the two recognizing branches, the dual-recognizing peptide-based biosensor exhibited significantly enhanced sensitivity. Under the optimal experimental conditions, the biosensor for IgG exhibited a linear response range of 0.1 pg/mL to 0.1 μg/mL, with a limit of detection of 0.031 pg/mL (about 2 orders of magnitude lower than that of the normal biosensor). Moreover, the biosensor was also capable of assaying IgG in real biological samples such as human serum without suffering from significant biofouling. This strategy for biosensor construction not only ensures the ultra-sensitivity for target detection, but also effectively avoids biofouling on sensing interfaces in complex biological media.
本文提出了一种基于具有两个针对单一目标的识别分支的设计多功能肽的抗污染电化学生物传感器，以提高目标识别效率和灵敏度。设计的多功能肽包含两个针对免疫球蛋白 G（IgG）的不同识别分支（序列为 FYWHCLDE 和 FYCHTIDE）、一个抗污染序列（EKEKEK）和一个锚固序列（CPPPP），可以固定在金纳米粒子（AuNPs）和聚（3,4-亚乙基二氧噻吩）（PEDOT）修饰的电极表面。由于两个识别分支的协同作用，基于双识别肽的生物传感器表现出显著增强的灵敏度。在最佳实验条件下，该 IgG 生物传感器的线性响应范围为 0.1 pg/mL 至 0.1 μg/mL，检测限为 0.031 pg/mL（约比普通生物传感器低 2 个数量级）。此外，该生物传感器还能够在没有受到明显生物污染的情况下检测人血清等真实生物样品中的 IgG。这种生物传感器构建策略不仅确保了对目标检测的超高灵敏度，而且还能有效避免复杂生物介质中传感界面的生物污染。
