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In this article the standard free energies (ΔG t 0 (i)) and entropies (ΔS t 0 (i)) of transfer of four homologous α-amino acids including glycine (Gly), DL-alanine (DL-Ala), DLα-amino butyric acid (DL-Aba.) and DL-nor-valine (DL-n-Val) from ethylene glycol (EG) to nonaqueous mixtures of ethylene glycol and dimethyl sulfoxide (DMSO) at 298.15 K are reported. The Gibbs energies of solutions have been determined from solubility measurements of each amino acid at different temperatures, that is, from 288.15 to 308.15 K by "formol titrimetry". The chemical parts of free energies (ΔG t,ch 0 (i)) and entropies (TΔS t,ch 0 (i)) of transfer of the homologous α-amino acids have been computed by subtracting the cavity effects and dipole−dipole interaction effects from the total transfer energies. The characteristics of the solvation thermodynamics of α-amino acids in EG-DMF and EG-ACN mixed solvent systems studied earlier are also discussed here for comparison.

Standard free energies (t) and entropies (t) of transfer of some homologous α-amino acids viz. glycine (gly), Dl-alanine (ala), Dl-α-amino butyric acid (aba) and Dl-nor-valine (nor-val) from protic ethylene glycol (EG) to dipolar aprotic N,N-dimethyl formamide (DMF) have been evaluated from solubility measurements at five equidistant temperatures i.e. from 15˚C to 35˚C. The observed t and t vs composition profiles are complicated because of the various interaction effects. The chemical effects of the transfer Gibbs energies (t ch ,

Solvation thermodynamic data of dl-serine and dl-phenylalanine in aqueous mixtures of dimethylsulfoxide at 298.15 K were determined from solubility measurement.

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