Nitrogen-Doped Carbonized Polymer Dots: A Potent Scavenger and Detector Targeting Alzheimer's β-Amyloid Plaques

The fibrillization and deposition of beta-amyloid protein (A beta) are recognized to be the pathological hallmarks of Alzheimer's disease (AD), which signify the need for the effective detection and inhibition of A beta accumulation. Development of multifunctional agents that can inhibit A beta aggregation, rapidly disaggregate fibrils, and image aggregates is one of the effective strategies to treat and diagnose AD. Herein, the multifunctionality of nitrogen-doped carbonized polymer dots (CPDs) targeting A beta aggregation is reported. CPDs inhibit the fibrillization of A beta monomers and rapidly disintegrate A beta fibrils by electrostatic interactions, hydrogen-bonding and hydrophobic interactions with A beta in a time scale of seconds to minutes. Moreover, the interactions make CPDs label A beta fibrils and emit enhanced red fluorescence by the binding, so CPDs can be used for in vivo imaging of the amyloids in transgenicCaenorhabditis elegansCL2006 as an AD model. Importantly, CPDs are demonstrated to scavenge the in vivo amyloid plaques and to promote the lifespan extension of CL2006 strain by alleviating the A beta-triggered toxicity. Taken together, the multifunctional CPDs show an exciting prospect for further investigations in A beta-targeted AD treatment and diagnosis, and this study provides new insight into the development of carbon materials in AD theranostics.