Label-free methods for probing the interaction of Clioquinol with Amyloid-β

The presence of amyloid-β (Aβ) fibrils is characteristic of Alzheimer's disease (AD), and the aggregation of these amyloidogenic proteins is a nucleation-dependent process. In this report, label-free methods based on surface plasmon resonance (SPR) and thickness shear mode acoustic wave sensors (TSM-AWS) were used to detect monomer elongation in real-time. The modulation of Aβ aggregation using a well-described flavonoid, clioquinol (CQ) was also observed. Established methods like fluorescence and electrochemistry were also employed to confirm the interaction of CQ with Aβ. Good correlation between the designed label-free methods creates a promising platform for the screening of novel amyloid inhibitors. © 2012 The Royal Society of Chemistry.