Journal of Chemical Thermodynamics, Vol.38, No.2, 136-143, 2006
Volumetric, viscometric, and refractive index behaviour of alpha-amino acids and their groups' contribution in aqueous D-glucose solution at different temperatures
Density, rho, viscosity, eta, and refractive index, n(D) measurements have been carried out on alpha-amino acids, glycine, DL-alanine, L-serine, and DL-valine (0.1 to 0.5) M in 0.2 M aqueous D-glucose solution at T = (298.15 303.15, 308.15, and 313.15) K. These measurements have been performed to evaluate some important parameters, viz, apparent molar volume, phi(v). limiting apparent molar volume, phi(o)(v) transfer volume, phi(o)(v)(tr), viscosity A and B-coefficients of Jones-Dole equation, variation of B with temperature, dB/dT, free energy of activation per mole of solvent, Delta mu(o#)(1), and solute, Delta mu(o#)(2), respectively, and molar refractive index, R-D. These parameters have been interpreted in terms of solute-solute and solute-solvent interactions and structure making/breaking ability of solutes in the given solution. In addition to this, phi(o)(v), B-coefficient and Delta mu(o#)(2), have been split into group contributions NH3+, COO-, and CH2 of the amino acids using their linear correlation with number of carbon atoms in the alkyl chain of the amino acids. (C) 2005 Elsevier Ltd. All rights reserved.
Keywords:amino acids;glucose;partial molar volume;B-coefficient;transfer volume;groups' contribution