A new perylenediimide with NH functionality as a colorimetric and fluorescent probe for the selective detection of trivalent Fe3+ and Al3+ ions

We report the synthesis of a new colorimetric probe RI, in which the perylene tetracarboxylicdiimide fluorophore is connected with an adamantly amine unit through the NH binding site. RI was tested with a variety of metal ions and exhibited a significant colorimetric transition in the presence of Fe3+ and Al3+ ions. No significant changes were observed with other metal ions. Absorption measurements indicated that trivalent metal ions Fe3+/Al3+ bind with RI and generate a stable complex. The presence of Fe3+ and Al3+ ions induces new absorption bands with shoulder peaks at 525 nm and 568 nm. The fluorescence intensity of R1 at 579 nm was significantly increased by the addition of Fe(3+)or Al3+ ions. Furthermore, RI was found to be sensitive towards these metal ions at micromolar concentrations. The stoichiometry of RI :Fe3+/Al3+ complexes were confirmed by ESI-MS analysis, and binding constants were calculated using Benesi-Hildebrand plots. The binding mode of RI with metal ions was proposed based on optimized structure from DFT calculation. (C) 2017 Elsevier B.V. All rights reserved.