Electrochemical quantification of the Alzheimer’s disease amyloid-β (1-40) using amyloid-β fibrillization promoting peptide
Electrochemical quantification of the Alzheimer’s disease amyloid-β (1-40) using amyloid-β fibrillization promoting peptide
复制标题
使用淀粉样蛋白-β 纤维化促进肽对阿尔茨海默病淀粉样蛋白-β (1-40) 进行电化学定量
DOI：
10.1016/j.sbsr.2015.09.001
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发表时间：
2015
影响因子：
5.3
通讯作者：
and Hitoshi Abe
中科院分区：
文献类型：
--
作者：
Satoshi Fujii;Daiki Sono;Kaoru Matsubara;and Hitoshi Abe
淀粉样β肽（Aβ）被认为是早期诊断阿尔茨海默病的重要生物标志物。因此，人们一直渴望实用可靠的方法来测定Aβ水平。本研究建立了一种快速、灵敏、选择性高的肽修饰金电极上铜离子氧化还原循环检测Aβ（1-40）的电化学方法。将一种19个氨基酸残基的促Aβ纤维化肽（AFPP）固定在金电极上。在将Aβ溶液与修饰电极孵育1 h后，加入Cu 2+溶液并进行循环伏安法测量。Aβ（1-40）浓度在0.1-5 μM范围内与伏安响应呈线性关系，检出限为18 nM。用氢氧化钠和乙二胺四乙酸盐溶液洗涤可以很容易地使修饰电极重新初始化。使用重新初始化的电极获得的结果显示出良好的再现性。此外，当使用另一种淀粉样蛋白和Cu 2+结合蛋白胰淀素作为靶标时，没有观察到伏安响应。这些结果表明AFPP修饰电极为Aβ的定量提供了一种有前途的、无标记的、灵敏的、选择性的、成本有效的和简单的方法。
Amyloid-β peptide (Aβ) is believed to be an important biomarker for the early diagnosis of Alzheimer’s disease. Therefore, practical and reliable methods to assay Aβ levels have been coveted. In this study, a rapid, sensitive, and selective electrochemical method for Aβ(1–40) detection using Cu2+redox cycling on peptide-modified gold electrodes was developed. A 19-residue peptide that can promote Aβ fibrillization (AFPP) was immobilized onto a gold electrode. After incubating an Aβ solution with the modified electrode for 1 h, a Cu2+solution was added and cyclic voltammetry measurements were conducted. The voltammetric response was found to be proportional to the Aβ(1–40) concentration in the 0.1–5 μM range, and a detection limit of 18 nM was achieved. Washing with sodium hydroxide and ethylenediaminetetraacetate solutions easily reinitialized the modified electrode. Results obtained using the reinitialized electrode showed good reproducibility. Furthermore, when another amyloidogenic and Cu2+-binding protein amylin was used as the target, no voltammetric response was observed. These results indicate that the AFPP-modified electrode provides a promising, label-free, sensitive, selective, cost-effective, and easy method for the quantification of Aβ.