Direct visualization of β-amyloid fibrils with a self-powered imaging strategy through the generation of fluorescent tags with Pt nanozymes

Abstract

Aggregation of β-amyloid (Aβ) peptides plays a critical role in the pathogenesis of Alzheimer’s disease (AD). Visualizing Aβ1-40 aggregates is therefore essential for the understanding of pathological mechanisms. However, labeling Aβ aggregates with regular fluorophores commonly suffers from poor photostability, low photobleaching resistance, and high background noise. In this work, we introduce a self-powered imaging (SPI) strategy by using Pt nanoparticles (PtNPs) as the nanozymes to catalyze the generation of fluorescent resorufin (Rf) as efficient fluorescent tags for Aβ1-40 aggregates imaging. Since the catalytic event is randomized at the single-molecule level, nanoscopic imaging of Aβ1-40 aggregates is successfully realized through the single-molecule localization microscopy. The inhibitory effect of photosensitizers on Aβ1-40 fibrillation process is therefore imaged with nanoscale resolution. The SPI strategy introduced herein provides a promising catalysis-based method for Aβ1-40 fibrillation imaging.