Gold Nanoparticles as a Probe for Amyloid-? Oligomer and Amyloid Formation.

ABSTRACT: The process of amyloid-? (A?) amyloid formation is pathologically linked to Alzheimer's disease (AD). The identification of A? amyloids and intermediates that are crucial players in the pathology of AD is critical for exploring the underlying mechanism of A? aggregation and the diagnosis of the disease. Herein, we performed a gold nanoparticle (AuNP)-based study to detect the formation of A? amyloid fibrils and oligomers. Our results demonstrate that the intensity of the surface plasmon resonance (SPR) absorption band of the AuNPs is sensitive to the quantity of A?40 amyloids. This allows the SPR assay to be used for detection and semi-quantification of A?40 amyloids, and characterization of the kinetics of A? amyloid formation. Furthermore, our study demonstrates that the SPR band intensity of the AuNPs is sensitive to the presence of oligomers of both A?40 and an A?40 mutant, which forms more stable oligomers. The kinetics of the stable oligomer formation of the A?40 mutant can also be monitored following the SPR band intensity change of AuNPs. Our results indicate that this nanoparticle based method can be used for mechanistic studies of early protein self-assembly and fibrillogenesis.

SUBMITTER: Elbassal EA 

PROVIDER: S-EPMC5737797 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature