Ternary mutual diffusion coefficients (D-11, D-22, D-12 and D-21) measured by the Taylor dispersion method are reported for aqueous solutions of {levodopa (L-dopa) + beta-cyclodextrin (beta-CD)} solutions at T = 298.15 K and concentrations up to 0.007 mol . dm (3). Significant effects on the diffusion were observed, suggesting interactions between this carbohydrate and L-dopa. Support for this came from H-1 NMR spectroscopy, which shows that these effects are due to formation of 1:1 (beta-CD:L-dopa) complexes. (C) 2015 Elsevier Ltd. All rights reserved.