Thermo-physical properties of l-Alanine/l-Valine in aqueous solutions of non steroid anti inflammatory drug dolonex at different temperatures: Volumetric and acoustic approach

Thermodynamic properties of l-Alanine and l-Valine in aqueous solutions of drug dolonex, have been investigated by combination of volumetric and acoustic methods at various temperatures (293.15, 298.15, 303.15, 308.15 and 313.15) K and at atmospheric pressure. The experimental data is further used to calculate limiting apparent molar volume, VoΦ, limiting apparent molar volume of transfer, VoΦ,tr, limiting molar isentropic compression, KoΦ,S and limiting apparent molar isentropic compression of transfer, KoΦ,S,tr. Furthermore, apparent molar expansivity, EoΦ, Hepler constant values, ∂EΦo∂TP, coefficient of thermal expansion, α and hydration number, nH were also calculated. The obtained results were used to interpret solute-solute and solute-solvent interactions in these systems. The volumetric and compressibility data suggests dominance of hydrophilic-hydrophilic interactions in these systems.