Pulse light and pH jumps were used to study the structural transformations of the 4′,7-dihydroxyflavylium cation when involved in ion-pairs with the anions chloride, bromide and perchlorate. The association constants of the ion-pairs were calculated by a new approach based on two spectrophotometric titrations; (i) in the absence and. (ii) in the presence of a constant concentration of co-pigment. This method was also used to calculate the ion-pairing association constants of Malvin and the same anions. On the basis of our results, the co-pigmentation model based on the suppression of the hydration reaction in the flavylium complex is questioned.
|Number of pages||6|
|Journal||Journal of Photochemistry and Photobiology A: Chemistry|
|Publication status||Published - 31 Mar 1998|