A new fluorene-bearing pyridine-2,6-dicarboxamide (3) as an effectint fluorescent and colorimetric cation sensor was successfully synthesized and well-characterized using FT-IR, NMR, ESI+-MS and elemental analysis. The metal ion binding ability of the chemosensor 3 in the presence of different metal ions was investigated using UV–vis, fluorescence experiments and results exhibited a desirable selectivity and significant sensitivity of the chemosensor 3 for the detection of Cu2+ and Pb2+ ions. The association constant (Ka) of 3-Cu2+ and 3-Pb2+ complexes were determined to be 8.89 × 103 M− 1 and 5.65 × 108 M-2, respectively. The obtained limit of detection (LOD) values (1.49 × 10− 6 M for Cu2+ and 2.31 × 10− 6 M for Pb2+) clearly revealed the considerable sensitivity of the chemosensor 3.
