title: Limiting values of diffusion coefficients of glycine, alanine, α-amino butyric acid, norvaline and norleucine in a relevant physiological aqueous medium.
abstract: 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.
authors.affiliation: Departamento de Química, Facultad de Ciencias, Universidad Nacional de Colombia Sede Bogotá, Calle 44 No. 45-67, Bloque B-09, Bogotá D.C., Colombia.
authors.forename: Diana M
authors.initials: DM
authors.lastname: Rodriguez
authors.affiliation: Department of Chemistry, University of Coimbra, 3004-535, Coimbra, Portugal.|U.D. Química Física, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain.
authors.forename: Luis M P
authors.initials: LM
authors.lastname: Verissimo
authors.affiliation: Department of Chemistry, University of Coimbra, 3004-535, Coimbra, Portugal.|U.D. Química Física, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain.
authors.forename: Marisa C F
authors.initials: MC
authors.lastname: Barros
authors.affiliation: Department of Chemistry, University of Coimbra, 3004-535, Coimbra, Portugal.
authors.forename: Daniela F S L
authors.initials: DF
authors.lastname: Rodrigues
authors.affiliation: U.D. Química Física, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain.
authors.forename: Maria Melia
authors.initials: MM
authors.lastname: Rodrigo
authors.affiliation: Department of Chemistry, University of Coimbra, 3004-535, Coimbra, Portugal.|U.D. Química Física, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Esteso
authors.affiliation: Departamento de Química, Facultad de Ciencias, Universidad Nacional de Colombia Sede Bogotá, Calle 44 No. 45-67, Bloque B-09, Bogotá D.C., Colombia.
authors.forename: Carmen M
authors.initials: CM
authors.lastname: Romero
authors.affiliation: Department of Chemistry, University of Coimbra, 3004-535, Coimbra, Portugal. anacfrib@ci.uc.pt.
authors.forename: Ana C F
authors.initials: AC
authors.lastname: Ribeiro
mesh_terms: D000409:Alanine / Q000737:chemistry*; D020148:Butyric Acid / Q000737:chemistry; D004058:Diffusion; D005998:Glycine / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D009646:Norleucine / Q000737:chemistry*; D009994:Osmolar Concentration; D014633:Valine / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D020148:Butyric Acid; D009646:Norleucine; C005313:norvaline; D014633:Valine; D000409:Alanine; D005998:Glycine
keywords: Topical Issue: Non-isothermal transport in complex fluids