Synthesis of methionine methyl ester-modified coumarin as the fluorescent-colorimetric chemosensor for selective detection Cu with application in molecular logic gate.

A methionine methyl ester-modified coumarin derivative was designed and synthesized, which could discriminate Cu from other metal ions in HEPES buffer (10 mM, pH 7.4)/CHCN (40:60, V/V). The detection limit of WM toward Cu was 1.84 × 10 M, which was lower than the concentration of Cu in drinking water suggested by WHO and EPA. And the proposed coordination mode exhibiting the interaction between WM and Cu was studied by UV-Vis, fluorescence spectrum, ESI-MS and FT-IR. Based on the fluorescent reversibility of WM, WM was considered as a molecular logic gate and molecular keypad lock. In addition, the test strips and the silica gel plates prepared from the solution of WM also demonstrate the favorable selectivity toward Cu.