Novel D–π-A type near-infrared fluorescent probes for the detection of Aβ40 aggregates

Abstract

Aberrant accumulation of Amyloid-β (Aβ) peptide is closely related to Alzheimer's disease. Thus, it is important to develop featured probes for the specific detection of Aβ species. Herein, we designed and synthesized a novel near-infrared fluorescent probe SDPY based on the D–π-A architecture for the detection of Aβ aggregates. The probe SDPY displayed higher affinity for Aβ₄₀ aggregates over Aβ₄₂ aggregates in solution (K_d = 164 nM vs. 2.1 μM). In addition, SDPY showed excellent anti-interference against a wide range of other substances. Furthermore, SDPY was capable of labeling Aβ₄₀ aggregates better than Aβ₄₂ aggregates in the brain sections of AD transgenic mouse models.