Abstract (EN):
A novel bioinspired 10-methylpyranoflavylium dye was synthesized. The dye was fully characterized by LC-DAD/ESI-MS and NMR 1D and 2D techniques, and its equilibrium constants towards pH variations were determined by UV-vis titration. These studies revealed the presence of three species (a flavylium cation AH(+) , a neutral quinoidal base A, and an anionic quinoidal base A(-)) in the pH range 1-12, driven by the two pK(a)values of the dye: pK(a1)= 6.8 +/- 0.1 and pK(a2)= 10.8 +/- 0.1. The first deprotonation of the dye occurs within the pH range for spoilage of many packed-food products, making the dye an excellent candidate for use as a pH sensor for real-time monitoring of the quality and freshness of foods.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
5