A theoretically improved perturbation model for activity coefficients of amino acids and peptides in aqueous solutions

被引:28
作者
Khoshkbarchi, MK
Vera, JH
机构
[1] McGill Univ, Dept Chem Engn, Montreal, PQ H3A 2B2, Canada
[2] Hyprotech Ltd, Calgary, AB T2E 2R2, Canada
关键词
D O I
10.1021/ie970806g
中图分类号
TQ [化学工业];
学科分类号
0817 ;
摘要
A theoretically improved model, based on the perturbation theory, to correlate the activity coefficients of amino acids and peptides in aqueous solutions is presented. The radial distribution function for the reference system and for the perturbation term have been Obtained from the solution of the Percus-Yevick equation for hard sphere systems. The pair interaction energies required by the model are those due to dispersion forces and dipole-dipole interactions. These interactions are represented by a Lennard-Jones (6-12) and a Keesom expression, respectively. The depth of potential well in the Lennard-Jones model and the size parameter of hard spheres were evaluated by the minimization of the Helmholtz free energy of the systems, The significance of the parameters is justified by comparison of the model with the Gibbs-Bogoliubov inequality. Independently evaluated dipole moments of the amino acids are used. The model can accurately correlate the activity coefficients of amino acids and peptides in aqueous solutions over a wide range of concentration.
引用
收藏
页码:3052 / 3057
页数:6
相关论文
共 18 条
[1]  
[Anonymous], PROTEINS AMINO ACIDS
[2]   PERTURBATION THEORY AND EQUATION OF STATE FOR FLUIDS .2. A SUCCESSFUL THEORY OF LIQUIDS [J].
BARKER, JA ;
HENDERSO.D .
JOURNAL OF CHEMICAL PHYSICS, 1967, 47 (11) :4714-&
[3]   MEAN SPHERICAL MODEL FOR ASYMMETRIC ELECTROLYTES .2. THERMODYNAMIC PROPERTIES AND PAIR CORRELATION-FUNCTION [J].
BLUM, L ;
HOYE, JS .
JOURNAL OF PHYSICAL CHEMISTRY, 1977, 81 (13) :1311-1317
[4]   EQUATIONS OF STATE FOR MIXTURES OF SQUARE-WELL MOLECULES - PERTURBATION AND LOCAL COMPOSITION THEORIES FOR BINARY-MIXTURES OF EQUAL-SIZED MOLECULES [J].
BOKIS, CP ;
DONOHUE, MD .
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 1995, 34 (12) :4553-4561
[5]  
Fasman G D., 1976, Handbook of biochemistry and molecular biology, V1
[6]  
Greenstein JP, 1961, CHEM AMINO ACIDS, V1
[7]   PERTURBATION-THEORY AND EXCESS PROPERTIES OF MIXTURES OF SIMPLE LIQUIDS [J].
GRUNDKE, EW ;
HENDERSON, D ;
BARKER, JA ;
LEONARD, PJ .
MOLECULAR PHYSICS, 1973, 25 (04) :883-896
[8]  
Hansen J.-P., 2006, THEORY SIMPLE LIQUID
[9]   PERTURBATION-THEORY FOR A MIXTURE OF HARD SPHERES AND SQUARE-WELL MOLECULES [J].
HENDERSON, D .
JOURNAL OF CHEMICAL PHYSICS, 1974, 61 (03) :926-931
[10]   A simplified perturbed hard-sphere model for the activity coefficients of amino acids and peptides in aqueous solutions [J].
Khoshkbarchi, MK ;
Vera, JH .
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 1996, 35 (11) :4319-4327