Premium
Analysis of the Statistical Thermodynamic Model for Nonlinear Binary Protein Adsorption Equilibria
Author(s) -
Zhou XiaoPeng,
Su XueLi,
Sun Yan
Publication year - 2007
Publication title -
biotechnology progress
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.572
H-Index - 129
eISSN - 1520-6033
pISSN - 8756-7938
DOI - 10.1021/bp070092x
Subject(s) - adsorption , ionic strength , thermodynamics , binary number , chemistry , nonlinear system , component (thermodynamics) , ionic bonding , nonlinear regression , bovine serum albumin , binary system , chromatography , ion , mathematics , organic chemistry , regression analysis , aqueous solution , physics , statistics , arithmetic , quantum mechanics
The statistical thermodynamic (ST) model was used to study nonlinear binary protein adsorption equilibria on an anion exchanger. Single‐component and binary protein adsorption isotherms of bovine hemoglobin (Hb) and bovine serum albumin (BSA) on DEAE Spherodex M were determined by batch adsorption experiments in 10 mM Tris‐HCl buffer containing a specific NaCl concentration (0.05, 0.10, and 0.15 M) at pH 7.40. The ST model was found to depict the effect of ionic strength on the single‐component equilibria well, with model parameters depending on ionic strength. Moreover, the ST model gave acceptable fitting to the binary adsorption data with the fitted single‐component model parameters, leading to the estimation of the binary ST model parameter. The effects of ionic strength on the model parameters are reasonably interpreted by the electrostatic and thermodynamic theories. The effective charge of protein in adsorption phase can be separately calculated from the two categories of the model parameters, and the values obtained from the two methods are consistent. The results demonstrate the utility of the ST model for describing nonlinear binary protein adsorption equilibria.