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Photocatalytic Eosin Y mediated single electron transfer for spatially resolved proteomics of amyloid aggregates in Alzheimer’s disease

ABSTRACT: Alzheimer’s disease (AD) is characterized by the accumulation of pathological amyloid aggregates, yet methods for spatially resolved, proteome-wide profiling of amyloid composition and their microenvironment remain limited. Here, we report Eosin Y (EY) as an easily accessible and efficient organic photocatalyst for pan-amyloid binding, labeling, and proteomic profiling in AD brain tissues. EY demonstrated strong binding affinity toward various amyloids. Upon green-light irradiation in the presence of aryl azide, EY enabled rapid and covalent labeling of amyloid structures and this process was demonstrated to be a single-electron transfer (SET) pathway. Application of this strategy to 5×FAD mouse brain tissue enabled successful enrichment and proteomic identification of key AD related proteins, including App, Apoe, and Gfap. Together, this work demonstrates a microscopy free method for the molecular dissection of amyloid plaques, advancing the toolbox for neurodegenerative disease research

ORGANISM(S): Mus Musculus

SUBMITTER: Yu Liu

PROVIDER: PXD070935 | iProX | Wed Nov 19 00:00:00 GMT 2025

REPOSITORIES: iProX

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