School of Chemistry and Molecular Engineering, Shanghai Key Laboratory for Urban Ecological Processes and Eco-Restoration, East China Normal University, 500 Dongchuan Road, Shanghai 200241, People's Republic of China.
Analyst. 2020 Mar 21;145(6):2331-2338. doi: 10.1039/c9an02285f. Epub 2020 Feb 7.
Ultrasensitive detection of monomeric β-amyloid peptides is of fundamental significance for studying the pathological progression of Alzheimer's disease (AD). In this article, by facilely engineering a gold microelectrode interface, we developed a novel electrochemical biosensor for sensitive and selective monitoring of β-amyloid peptide (Aβ) monomers in cerebrospinal fluid (CSF). Through specific Cu-Aβ-hemin coordination, Aβ directed the assembly of Cu-PEI/AuNPs-hemin nanoprobes into network aggregates on a microelectrode interface, which promoted the enrichment of Aβ monomers on the microelectrode. Furthermore, the AuNP aggregate promotes the deposition of silver nanoparticles, which were utilized for the electrochemical stripping analysis of the Aβ monomer. The proposed method displayed ultra-sensitivity for Aβ monomers with the detection limit down to 0.2 pM. Besides, high selectivity toward Aβ monomers was observed. These remarkable analytical performances render the electrochemical biosensor useful for evaluating the dynamic change of Aβ monomer level in CSF of live mice with AD, promoting the investigation of the role that Aβ monomers play in brain events.
单体β-淀粉样肽的超敏检测对研究阿尔茨海默病（AD）的病理进展具有重要意义。在本文中，通过简单地工程化金微电极界面，我们开发了一种新型电化学生物传感器，用于灵敏和选择性监测脑脊液（CSF）中的β-淀粉样肽（Aβ）单体。通过特异性的 Cu-Aβ-血红素配位，Aβ引导 Cu-PEI/AuNPs-血红素纳米探针在微电极界面上组装成网络聚集物，从而促进 Aβ单体在微电极上的富集。此外，AuNP 聚集物促进了银纳米粒子的沉积，可用于 Aβ单体的电化学剥离分析。所提出的方法对 Aβ单体具有超灵敏性，检测限低至 0.2 pM。此外，还观察到对 Aβ单体的高选择性。这些显著的分析性能使得电化学生物传感器可用于评估 AD 活鼠 CSF 中 Aβ单体水平的动态变化，从而促进对 Aβ单体在大脑事件中作用的研究。
