摘要

A terthiophene carboxylic derivative, 3,3 ''-dihexyl-2,2':5',2 ''-terthiophene-5-carboxylic acid (3TC6A), was synthesized and its application as fluorescent biosensor was investigated using Bovine Serum Albumin (BSA) and Lectin from Triticum as the target proteins. The photophysical properties of terthiophene carboxylic acid depend on the solvent polarity and the pH of the solution. At low concentrations, the dye exhibits monomer emission in organic solvents. In acidic and neutral aqueous solutions, it displays dimer emission (490-500 nm). The emission can be completely quenched by heptyl viologen in aqueous solutions due to intermolecular electron transfer. While no emission enhancement was observed in the presence of cytochrome C, hemoglobin, or lysozyme, upon binding to trace amounts of BSA, the dye displayed strongly enhanced monomer emission at 450 nm. Upon binding to Lectin from Triticum vulgaris, the dye displayed enhanced dimer emission at 490 nm. In both cases, the fluorescence intensity is proportional to the concentration of proteins, making this organic dye a promising reagent for protein analysis.

  • 出版日期2016-5