Binary Mutual Diffusion Coefficients of Aqueous Solutions of α-Cyclodextrin, 2-Hydroxypropyl-α-cyclodextrin, and 2-Hydroxypropyl-β-cyclodextrin at Temperatures from (298.15 to 312.15) K

Abstract

Binary mutual diffusion coefficients measured by the Taylor dispersion method are reported for aqueous solutions of α-cyclodextrin (α-CD), 2-hydroxypropyl-α-cyclodextrin (HP-α-CD), and 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) at concentrations from (0.002 to 0.010) mol·dm-3 at temperatures from (298.15 to 312.15) K. The hydrodynamic radius and activation energy for the diffusion of aqueous α-CD, HP-α-CD, and HP-β-CD are calculated from the experimental results. In addition, the Hartley equation and the measured diffusion coefficients are used to estimate activity coefficients for aqueous α-CD, HP-α-CD, and HP-β-CD.