Development of Ru-polypyridyl complexes for real-time monitoring of Aβ oligomers and inhibition of Aβ fibril formation†

The aggregation of amyloid-β (Aβ) is one of the important pathological markers of Alzheimer's disease. Ruthenium(II) complexes have good stability, low cytotoxicity, a high fluorescence quantum yield, and a good Stokes shift as fluorescent probes. Based on this, we constructed a fluorescent probe for in vivo real-time imaging and inhibition of Aβ-fibril formation using a complex of Ru polypyridine with organic fluorophores (N,N-dimethylaniline) and hydrophobic peptides (KLVFF). DLS and TEM studies have shown that Ru-YH has an inhibitory effect on the fibrotic aggregation of Aβ. Both in vivo and in vitro studies have shown that Ru-WJ and Ru-YH can quickly cross the blood–brain barrier and successfully detect Aβ in early (2.5-month old) transgenic mouse models. In summary, we have explored the potential of Ru complex based biological probes for early diagnosis and inhibition of AD.