Ultrasensitive Detection of Alzheimer’s Amyloids on a Plasmonic-Gold Platform

Abstract

More than 55 million people live with dementia worldwide in 2021, and there are nearly 10 million new cases every year. Alzheimer’s disease (AD) is the most common cause of dementia. Despite urgent need, early detection of AD and long-term monitoring of AD progression have been challenging. This is due to the limited availability of brain imaging facilities and the highly invasive procedure with the cerebrospinal fluid assay to assess the level of AD biomarkers, such as beta-amyloid (Aβ). Reliable measurements of AD biomarkers in blood samples are still difficult because of their very low abundance. Here, we develop a rapid, specific, and ultrasensitive immunoassay using plasmonic-gold nanoisland (pGOLD) chips with near-infrared fluorescence-enhanced detection for Aβ1–40 and Aβ1–42. We show step-by-step processes and results during the platform establishment, including antibody specificity and sensitivity tests, antibody pair examination, condition optimization, and procedure refinement. Finally, we demonstrate the platform performance with detection sensitivity at the subpicogram per milliliter level. This platform, therefore, has a great application potential for early detection of AD using blood samples.

Palladium nanoballs coupled with smartphone-thermal reader for photothermal lateral flow immunoassay of Aβ 1-40

“…[13][14][15] Unfortunately, the detection process of these techniques is too laborious and costly to be applied to point-of-care diagnosis. The past decade has seen the extensive development of several biosensors combined with colorimetric detection, [16][17][18][19] fluorescent detection, [20][21][22] and electrochemical detection, [23][24][25] for the direct detection of Ab 1-40 in serum. Of these methods, lateral flow strips (LFSs) are attracting increased interest for use in clinical laboratories and point-ofcare testing due to their quick assay performance, costeffectiveness, high flexibility, and the ease with which they can be delivered to end-users.…”

Label-free detection of Aβ-42: a liquid crystal droplet approach for Alzheimer's disease diagnosis

“…AD can easily be curable if it is identified at early stages. 1 In this regrading in medical different techniques as follows positron emission tomography (PET) and magnetic resonance imaging (MRI) are new techniques for detecting Alzheimer's disease. 2 In this technique diagnosis is only achievable after the illness has advanced, this procedure is both expensive and not easily available in all medicals, that is the last stage, which is impossible to cure and tough to treat.…”

Blood pressure and Alzheimer's disease: A review of meta-analysis

“…There are 55 million people affected by dementia worldwide ( 1 ). Alzheimer's disease (AD) is the most common cause of dementia, accounting for up to 75% of all dementia cases ( 2 ).…”