DCDAPH (Compound 2c), a novel smart near-infrared fluorescence (NIRF) probe, efficiently detects β-amyloid (Aβ) plaques with an excitation/emission wavelength (λ ex /λ em) of 597/665 nm in PBS. It demonstrates high affinity for Aβ aggregates, exhibiting a dissociation constant (Kd) of 27 nM and an inhibition constant (Ki) of 37 nM. Furthermore, DCDAPH exhibits favorable blood-brain barrier permeability, qualifying it as a suitable agent for both in vitro and in vivo detection of Aβ plaques [1].