A New Disubstituted Polyacetylene for the Detection of α ‐Amino Acids

New imidazole‐functionalized disubstituted polyacetylene was synthesized by utilizing the postfunctional strategy. In addition, its ability to sense copper ions and α ‐amino acids by fluorescence quenching has been studied. The quenching of the fluorescence of the imidazole‐functionalized disubstituted polyacetylene was observed at a very low level of Cu 2+ (7.0 × 10 −7 mol · L −1 ). The fluorescent intensity decreased rapidly upon the increase of the concentration of the added solution of Cu 2+ . It was expected that the addition of α ‐amino acids to the solution of the polyacetylene/Cu 2+ complex could turn on the fluorescence of the polyacetylene, if α ‐amino acids could remove the copper ions from the complex. Glycine, was used for testing: upon the addition of glycine the quenched fluorescence of P1 turned on immediately. The detection limit was as low as 6.0 × 10 −5 mol · L −1 .