Interactions of amino acids with aqueous solutions of hydroxypropyl-β-cyclodextrin at different temperatures: A volumetric and viscometric approach

• Densities and viscosities of solutions have been measured at different temperature and p = 100 MPa.
• The relevant parameters of volume and viscosity have been determined for the amino acids.
• The results are used to interpret the (solute + solute) and (solute + solvent) interactions.
• (Host + guest) interactions in these systems are also discussed.

Densities, ρρ, and viscosities, ηη for glycine, l-alanine, l-valine and l-phenyalanine in 0.01 mol · kg−1 aqueous solutions of hydroxypropyl-β-cyclodextrin have been measured at T = (293.15, 298.15, 303.15 and 308.15) K. From these experimental results, the apparent molar volume, VϕVϕ, limiting apparent molar volume, Vϕ0 and the slope, SVSV, transfer volume, ΔVϕ0, limiting apparent molar expansibility, ϕE0, hydration number, nHnH, Falkenhagen coefficient, A, and Jones–Dole coefficient, B, were calculated. The results are interpreted in terms of (solute + solvent) and (solute + solute) interactions in these systems. The trends in transfer volume ΔVϕ0 have been interpreted in terms of (solute + solvent) interactions based on a co-sphere overlap model and (host + guest) interactions.