Influence of fructose on the diffusion of potassium hydrogen phosphate in aqueous solutions at 25 °C

Abstract

Diffusion coefficients have been measured at 25°C for potassium hydrogen phosphate (K2HPO4, 0.101molkg−1) in aqueous solutions containing various concentrations of fructose from (0.001 to 0.101)molkg−1, using a conductimetric cell (the Lobo cell) coupled to an automatic data acquisition system. Significant effects of fructose were observed on the diffusion of K2HPO4 in these mixtures, which are attributed to the interaction between HPO42− anion (or other protonated forms) and fructose. Support for this comes from 1H and 13C NMR spectroscopy, which are compatible with binding between the anomeric forms of d-fructose and the HPO42− anion.