Electron microscopic analysis of nanoparticles delivering thioflavin-T after intrahippocampal injection in mouse: implications for targeting β-amyloid in alzheimer's disease

Abstract Prevention of β-amyloid (Aβ) production, aggregation and formation of Aβ deposits is a key pharmacological target in Alzheimer's disease. The passage of Aβ-binding compounds through the blood–brain barrier is often hampered for free ligands, whereas it is enhanced by drug encapsulation in nanoparticles. Here, we describe the preparation and characterization of polymeric carriers containing thioflavin-T as a marker for fibrillar Aβ. This study is then focused on electron microscopic analyses of thioflavin-T after injection of thioflavin-T-containing nanoparticles into the mouse hippocampus. Therefore, the photoconversion of fluorescent thioflavin-T as model drug was performed in tissues fixed 3 days post-injection. Thioflavin-T delivered from nanospheres was predominantly found in neurons and microglia. Our data suggest that drugs delivered by nanoparticles might target Aβ in the brain.