Alzheimer's disease: Development of a sensitive label-free electrochemical immunosensor for detection of amyloid beta peptide

SENSORS AND ACTUATORS B-CHEMICAL

卷:239

Article

Carneiro, Pedro^1,2  Loureiro, Joana¹  Delerue-Matos, Cristina²  Morais, Simone²  Pereira, Maria do Carmo¹ 

[1] Univ Porto, Fac Engn, Dept Chem Engn, LEPABE, Rua Dr Roberto Frias, P-4200465 Oporto, Portugal

[2] Inst Politecn Porto, Inst Super Engn Porto, REQUIMTE LAQV, R Dr Antonio Bernardino de Almeida 431, P-4200072 Oporto, Portugal

关键词: Alzheimer's disease;    beta-Amyloid peptide;    Electrochemical biosensor;    Self-assembled monolayer;    Gold nanoparticles;    Monoclonal antibody;   

DOI  :  10.1016/j.snb.2016.07.181

来源: Elsevier

【 摘 要 】

In this work, a highly sensitive label-free immunosensor for detection of the main biomarker of Alzheimer's disease (AD), amyloid beta 1-42 (A beta (1-42)), is presented. A gold electrode was modified with a mercaptopropionic acid (MPA) self-assembled monolayer, electrodeposited gold nanoparticles (AuNPs) and a monoclonal antibody mAb DE2B4 to recognize A beta; all the relevant experimental variables were optimized. Antibodies were functionalized through chemical modification (thiolation) to promote the antibody immobilization on the AuNPs surface with proper orientation which enabled the direct detection of A beta(1-42). Scanning electron microscopy, square-wave voltammetry and electrochemical impedance spectroscopy were used to characterize the construction of the biosensor. Using the proposed immunosensor, A beta(1-42) was specifically detected within the linear range of 10-1000 pgmL(-1) with a 5.2 pg mL(-1) and 17.4 pgmL(-1) detection and quantification limit, respectively; recovery values for the tested spiking levels ranged from 90.3 to 93.6%. The immunosensor enables rapid, accurate, precise, reproducible and highly sensitive detection (14.6%(reduction) ml-Pg(-1)) of Ap with low-cost and opens the possibilities for diagnostic ex vivo applications and research-based in vivo studies. (C) 2016 Elsevier B.V. All rights reserved.

【 授权许可】

Free