A fast, highly selective and sensitive dansyl-based fluorescent sensor for copper (II) ions and its imaging application in living cells

Since the copper ions (Cu2+) play a fatal role in many foundational physiological processes, it is important to develop a simple, highly sensitive and selective sensor for Cu2+ detection in living systems. Herein, an intramolecular charge transfer (ICT) and dansyl-based fluorescent chemosensor 1 was designed, synthesized and characterized for the sensitive and selective quantification of Cu2+. It exhibited remarkable fluorescence quenching upon addition of Cu2+ over other selected metal ions, attributed to the complex formation between 1 and Cu2+ with the association constant 6.7 x 10(5) M-1. The sensor 1 showed a fast and linear response towards Cu2+ in the concentration range from 0 to 12.5 x 10(-6) mol L-1 with the detection limit of 2.5 x 10(-7) mol L-1. This detection could be carried out in a wide pH range of 5.0-14. Furthermore, sensor 1 can be used for detecting Cu2+ in living cells. (C) 2017 Elsevier Ltd. All rights reserved.