A new fluorescence turn-on type chemosensor for Fe3+ based on naphthalimide and coumarin

A new Fe3+-selective turn-on chemosensor 1 based on coumarin and naphthalimide was designed and synthesized. The chemosensor exhibits high selectivity for Fe3+ over other ions (Mn2+, Co2+, Ni2+, Cu2+, Ag+, Cd2+, Pb2+, Ca2+, Al3+, Ba2+, Hg2+, Li+, Mg2+, Sr2+, Zn2+ and K+) with fluorescence-enhancement in THF-H2O solution. The binding ratio of 1-Fe3+ complex was determined to be 1:1 according to the Job plot. The association constant K-a of Fe3+ binding with sensor 1 was (2.589 +/- 0.206) x 10(3) M-1. The detection limit was calculated to be 0.388 mu M. (C) 2014 Elsevier Ltd. All rights reserved.