Physico-Chemical Studies of Glycine, L-Alanine, L-Phenylalanine and Glycylglycine in Aqueous Triton X-100 at Different Temperatures.

The densities, ς and viscosities, η of glycine (Gly), L-alanine (Ala), L-phenylalanine (Phe) and glycylglycine (Gly-Gly) in aqueous Triton X-100 (TX-100) solutions have been measured as a function of amino acid/peptide concentration at 298.15, 303.15, 308.15 and 313.15 K. The experimental data have been utilized to evaluate various thermodynamic parameters, viz., apparent molar volumes, V2, partial molar volumes at infinite dilution, V20, partial molar isobaric expansibilities, φE0, partial molar volumes of transfer, ΔtrV20 and A and B-coefficients of viscosity, respectively. The hydration numbers have also been calculated. The results have been discussed in terms of interactions taking place in the present systems. The structure-making/-breaking ability of the solute (amino acid/peptide) in the presence of surfactant, Triton X-100 has also been considered. [ABSTRACT FROM AUTHOR]