A novel near-infrared fluorescent platform with good photostability and the application for a reaction-based Cu(2+) probe in living cells.

Most of the near-infrared (NIR) fluorescent copper ion probes are coordination-based, and the fluorescence enhancement is between 10 and 20 folds. Herein, a novel NIR fluorescent dye named CSCN with excellent photostability and a reaction-based Cu(2+) NIR probe named CSCN-Cu were reported. CSCN exhibited good photostability toward photo irradiation. CSCN-Cu showed lower background fluorescent interference and over 40-fold fluorescence enhancement in NIR region, it also exhibited good selectivity toward Cu(2+) in Hepes solution. Biotic experiments demonstrated that CSCN-Cu possessed low toxicity and successfully imaged Cu(2+) in living cells under the conditions performed.