Nanoparticles targeting amyloid deposits: a potential contrast agent for diagnosis and treatment

Abstract

Amyloid-based diseases, such as amyloid light-chain amyloidosis, are characterized by misfolding of proteins and their deposition as amyloids in tissues. As prognosis is usually poor, patients suffering from these illnesses can benefit from improved detection, monitoring, and treatment techniques. The use of nanoparticles to diagnose and treat biological targets has been extensively studied, including as a potential marker for Alzheimer’s disease, but not in the context of amyloidosis. Although curcumin is a known amyloid-binding molecule, vanillin attachment to amyloids has not been proposed or tested in the past. Our study focuses on iron oxide and gold nanoparticles, functionalized with curcumin and vanillin, as potential agents for amyloid specific binding. These nanoparticles are designed to have high visibility in computed tomography or magnetic resonance imaging and can therefore facilitate improved imaging and monitoring of amyloids. Amyloid fibers and plaques were prepared from insulin, and the successful binding of the nanoparticles to the amyloids was demonstrated using optical, fluorescence, and transmission electron microscopy. The nanoparticles did not bind to amyloids placed in cell-culture models, suggesting good specificity.