A new highly effective fluorescent probe for Al3+ ions and its application in practical samples

A new 1,8-naphthalimide derivative, N-allyl-4-[3,3'((2-aminoethypazanediy1)-bis(N-(2-hydroxy-3methoxybenzylidene)propanehydrazide)]-1,8-naphthalimide (NBPN), was designed, synthesized and evaluated as a chemosensor for Al3+ ion. The structure of probe NBPN was established by single crystal Xray. Upon addition of different metal ions to the DMF/HEPES buffer (1:1, v/v, pH = 7.4) solution of NBPN, a significant selectivity toward Al3+ over other metal ions was observed. NBPN showed a good linearity with a correlation coefficient (R-2) of 0.95 in the concentration range 3-11 mu M. The respective detection limit of NBPN and the association constant for Al3+ were calculated to be 3.4 x 10(-8) M and 1 x 10(4) M-1. The stoichiometry and binding mode of probe NBPN with Al3+ were studied by spectroscopic methods of Job plot, UV-vis titration, fluorescence titration, MS and H-1 NMR titration and the experimental data indicated 1:1 stoichiometric complex between NBPN and Al3+. Ultimately, NBPN was employed for the detection of Al3+ in practical water samples. (C) 2016 Elsevier B.V. All rights reserved.