Autor: |
Rodriguez DM; Departamento de Química, Facultad de Ciencias, Universidad Nacional de Colombia Sede Bogotá, Calle 44 No. 45-67, Bloque B-09, Bogotá D.C., Colombia., Verissimo LM; Department of Chemistry, University of Coimbra, 3004-535, Coimbra, Portugal.; U.D. Química Física, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain., Barros MC; Department of Chemistry, University of Coimbra, 3004-535, Coimbra, Portugal.; U.D. Química Física, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain., Rodrigues DF; Department of Chemistry, University of Coimbra, 3004-535, Coimbra, Portugal., Rodrigo MM; U.D. Química Física, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain., Esteso MA; Department of Chemistry, University of Coimbra, 3004-535, Coimbra, Portugal.; U.D. Química Física, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain., Romero CM; Departamento de Química, Facultad de Ciencias, Universidad Nacional de Colombia Sede Bogotá, Calle 44 No. 45-67, Bloque B-09, Bogotá D.C., Colombia., Ribeiro AC; Department of Chemistry, University of Coimbra, 3004-535, Coimbra, Portugal. anacfrib@ci.uc.pt. |
Abstrakt: |
The side chain effect on transport in ionic aqueous salt solutions was investigated for [Formula: see text]-amino acids glycine, alanine, [Formula: see text]-amino butyric acid, norvaline, and norleucine --that together define a chemical homologous series based on the length of the characteristic side chain which increases from zero to four carbons, respectively. Binary mutual diffusion coefficients at infinitesimal concentration in aqueous solutions of NaCl (0.15 mol kg -1 ) are measured by means of Taylor dispersion technique for this series and significant differences were found against previous published results for identical systems in pure water. In this way, NaCl effect on the transport of each amino acid is thus assessed and discussed in terms of salting-out effects. Also, solvated Stokes hydrodynamic radii were computed for the series showing comparable results in water and NaCl solution. The new information should prove useful in the design and characterization of transport-controlled systems in physiological and pharmacological studies. |