Selenocysteine detection and bioimaging in living cells by a colorimetric and near-infrared fluorescent turn-on probe with a large stokes shift.

Selenocysteine (Sec) has emerged as an important sensing target in recent years. In this paper, a colorimetric and near-infrared fluorescent turn-on probe for Sec was developed. This probe features a remarkable large Stokes shift (146nm) and shows a rapid, highly selective detection process for Sec with obvious colorimetric and near-infrared fluorescent (Em 706nm with Ex 560nm) turn-on responses. In addition, this probe can be used to quantitatively detect Sec with high sensitivity with a detection limit of 62nM over a wide linear range (0.2-80μM). Moreover, it was further demonstrated that this NIR fluorescent probe can be employed to image both exogenous and endogenous Sec in living cells, indicating that this probe has great potential for biological applications.