Electrochemiluinescence monitoring the interaction between human serum albumin and amyloid-β peptide

Human serum albumin (HSA) is a major interaction-partner of amyloid- β (A β ) peptide in the plasma and can modulate the aggregation of A β . In this work, an efficient smart electrochemiluminescence (ECL) sensing platform was applied to determine the ability of HSA to bind different A β 40 aggregate species. Specifically, HSA was firstly adopted as a linker and self-assembled on the gold electrode, A β peptide were subsequently anchored onto the HSA-modified electrode through the recognition by HSA. CdS quantum dots (CdS QDs) modified with A β 40 aptamer as the ECL substrate were then captured on the electrode via the specific coordination between A β 40 and the aptamer. The present ECL sensor showed different ECL response in the presence of A β 40 with different aggregation states. The ECL platform exhibited a signal-on response with the introduction of A β 40 monomer in a concentration-dependent manner from 10 fM to 0.1 nM. Furthermore, the inhibition effect of several phenols on the aggregation of A β 40 was also investigated. This work potentially provided a feasible strategy of sensing platforms for A β detection and further understanding of the mechanism by which HSA modulates the aggregation of A β .