Partial Molar Volumes of Transfer of Some Amino Acids from Water to Aqueous Glycerol Solutions at 25°C.

Apparent molar volumes of glycine, DL-α-alanine, L-valine, L-leucine, and L-phenylalanine in 0.5, 1.0, 2.0, 3.5, and 5.0 m_B (mol-kg⁻¹) aqueous solutions of glycerol have been obtained from solution densities at 25°C using precise vibrating-tube digital densimeter. The estimated partial molar volumes at infinite dilution V^o ₂ have been used to obtain the corresponding transfer volumes Δ_tr V₂ ^o from water to different glycerol–water mixtures. The transfer volumes are positive for glycine and DL-α-alanine, and both positive and negative for the other amino acids over the concentration range studied. Interaction coefficients have been obtained from McMillan–Mayer approach and the data have been interpreted in terms of solute–cosolute interactions. [ABSTRACT FROM AUTHOR]