Electrochemical Immunosensors for Effective Evaluation of Amyloid-Beta Modulators on Oligomeric and Fibrillar Aggregation Processes

详细信息    查看全文

• 作者：Anthony J. Veloso ; Ari M. Chow ; Hashwin V. S. Ganesh ; Nan Li ; Devjani Dhar ; David C. H. Wu ; S. Mikhaylichenko ; Ian R. Brown ; Kagan Kerman
• 刊名：Analytical Chemistry
• 出版年：2014
• 出版时间：May 20, 2014
• 年：2014
• 卷：86
• 期：10
• 页码：4901-4909
• 全文大小：449K
• 年卷期：v.86,no.10(May 20, 2014)
• ISSN：1520-6882

文摘

A novel electrochemical immunosensor fabricated from gold compact disc electrodes was designed for rapid evaluation of aggregation processes that lead to the formation of oligomeric and fibrillar states of amyloid-beta_1鈥?2 (A尾_1鈥?2) during Alzheimer鈥檚 disease. Conformation-specific antibodies were immobilized on the surface of the gold electrode using a 3,3鈥?dithiobis (sulfosuccinimidyl) propionate (DTSSP) linker. Surface binding events were analyzed by electrochemical impedance spectroscopy (EIS) in which the formation of an antigen鈥揳ntibody complex was quantified as a function of charge transfer resistance using a [Fe(CN)₆]^{3鈥?4鈥?/sup> redox probe. The effectiveness of novel sym-triazine-derived aggregation modulators (TAE-1, TAE-2) to reduce the population of toxic oligomers was evaluated. A尾 fibril formation was validated by thioflavin T (ThT) fluorescence, whereas oligomer formation was investigated by MALDI. Antigen detection by EIS was further supported by immuno dot blot assays for oligomeric and fibrillar components. Docking simulations of the aggregation modulators TAE-1 and TAE-2 with A尾_1鈥?2 fibrils performed using Autodock Vina suggest a mechanism for the improved aggregation inhibition observed for TAE-2. The results demonstrate the utility and convenience of impedance immunosensing as an analytical tool for rapid and comprehensive evaluation of effective A尾 aggregation modulating agents.}