A NIR-emitting cyanine with large Stokes shifts for live cell imaging: large impact of the phenol group on emission

Abstract

There are a limited number of near-infrared (NIR) emitting (λ_em = 700–900 nm) molecular probes for imaging applications. A NIR-emitting probe that exhibits emission at ∼800 nm with a large Stokes shift was synthesized and found to exhibit excellent selectivity towards mitochondria for live-cell imaging. The photophysical properties were attributed to an excited “cyanine structure” via intramolecular charge transfer (ICT) involving a phenol group.