Recent advances in electrochemical biosensors for the detection of Aβ42, a biomarker for Alzheimer disease diagnosis

Alzheimer's disease (AD) is a progressive neurodegenerative disorder with a long latency in the "prodromal" stage, for which there are currently no effective treatments. It is generally accepted that accurate diagnosis and subsequent treatment in the early stages of AD may lead to better therapeutic outcomes. Detection of body fluid biomarkers is an effective strategy for early AD diagnosis. Among them, amyloid β(1–42) (Aβ42), as one of the most important biomarkers of AD, plays a key role in the progression of AD. Currently, electrochemical biosensors offer many advantages in monitoring Aβ42 because they are fast, portable, and capable of on-site analysis. This article provides an overview of the dynamics of Aβ42 levels in biological fluids as AD progresses, followed by a detailed description of the design and analytical performance of various electrochemical sensors. Finally, the challenges of electrochemical sensors for AD diagnosis are discussed, and prospects and trends are outlined.