Blood-based Alzheimer's disease diagnosis using fluorescent peptide nanoparticle arrays

There is a critical need to diagnose and monitor the progression of Alzheimer's disease (AD) using blood-based biomarkers. At present, it is believed that tau biomarkers can be utilized to reliably detect AD. Multimodal techniques are highly sought after for AD diagnosis and progression monitoring. For this purpose, we developed a fluorescent peptide nanoparticles (f-PNPs) arrays that is capable of detecting multiple signals simultaneously. The concentration, aggregation stages, and Young's modulus of tau biomarkers could be analyzed by monitoring the changes of multimodal fluorescence intensity, nano-morphological, and nano-mechanical properties of the f-PNPs arrays. Experimental results indicated that, compared to healthy human, the concentration, Young's modulus, and aggregation levels of tau proteins in blood samples of clinically diagnosed AD patients increased continuously with the increase of disease severity. The minimally invasive and multimodal characterization techniques showed high signal-to-noise ratio for AD diagnosis.