Hypochlorous Acid Activating MB‐O to Release Methylene Blue for Photodegrading of Aβ Aggregates

Abstract Amyloid‐β (Aβ) aggregates are one of biomarkers of Alzheimer's disease (AD). It is well known that Aβ aggregates display neurotoxicty or cytotoxicity to neurons. Thus, degrading Aβ aggregates is crucial for exploring the treatment of AD. Moreover, the excessive production of HOCl in the AD brain is an important feature of the disease. Herein, a novel compound MB‐O based on methylene blue (MB) skeleton was designed and synthesized. The probe MB‐O can specifically react with HOCl, releasing the fluorophore MB with strong fluorescence intensity increase. More importantly, the released MB is capable of degrading Aβ aggregates under red light irradiation.