Volumetric properties of amino acids in aqueous D-Xylose solutions at 298.15 K

Densities of glycine, L-alamne and L-serine in various aqueous D-xylose solutions were measured at 298.15 K by an Anton Paar Model 55 densimeter. Apparent molar volumes, limiting partial molar volumes and hydration numbers for these amino acids were calculated. The transfer volumes from water to aqueous D-xylose solutions were obtained and discussed in terms of the structural hydration interaction model. The results show that all of the transfer volumes are positive, and increase with increasing xylose concentration; the side-chain contributions to the transfer volumes are highly related to the nature of side-chain groups; the hydration numbers for the three amino acids in solutions decrease with increasing xylose concentration.