Calix[4]arene Based Highly Efficient Fluorescent Sensor for Au3+ and I-

This approach disclose the selective fluorogenic ion sensing ability of 5,11,17,23-tetratertbutyl-25,27-bis((2hydroxynaphthylimino)1,2-ethylenediaminecarbonylmethoxy)-26,28 dihydroxycalix[4]arene (C4NSB). Binding property of receptor probed by using selected various cations and anions with conferring of results that demonstrates 'turn-off' fluorescence response and significantly high chromogenic selectivity toward Au3+ and I-. Furthermore, selective nature of receptor was investigated in the presence of different co-existing competing ions. The limit of detection (LOD) for Au3+ and I- was determined as 1.5 x 10(-5) and 4.5 x 10(-6) M respectively. Receptor C4NSB form (1:1) stoichiometric complex with both ions and their binding constants were calculated as 8.0 x 10(2) for Au3+ and 15.6 x 10(2) M-1 for I-. Complexes were also characterized through FT-IR spectroscopy.