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) .