Effect of IDA and TREN chelating agents and buffer systems on the purification of human IgG with immobilized nickel affinity membranes.
The purification of IgG from human plasma was studied by comparing two affinity membranes complexed with Ni(II), prepared by coupling iminodiacetic acid (IDA) and Tris(2-aminoethyl)amine (TREN) to poly(ethylenevinyl alcohol), PEVA, hollow fiber membranes. The Ni(II)-TREN-PEVA hollow fiber membrane had lower capacity for human IgG than the complex Ni(II)-IDA-PEVA, but with similar selectivity. The IgG in peak fractions eluted from the Ni(II)-IDA-PEVA with a stepwise concentration gradient of Tris-HCl pH 7.0 (100-700 mM) reached a purity of 98% (based on IgG, IgM, IgA, albumin, and transferrin nephelometric analysis). Adsorption IgG data at different temperatures (4-37 degrees C) were analyzed using Langmuir model resulting in a calculated maximum capacity at 25 degrees C of 204.6 mg of IgG/g of dry membrane. Decrease in Kd with increasing temperature (1.7x10(-5) to 5.3x10(-6) M) indicated an increase in affinity with increased temperature. The positive value of enthalpy change (26.2 kJ/mol) indicated that the adsorption of IgG in affinity membrane is endothermic. Therefore, lower temperature induces adsorption as verified experimentally.
Ribeiro
Mariana Borsoi
MB
Department of Bioprocess Engineering, School of Chemical Engineering, State University of Campinas, UNICAMP, CP 6066, CEP 13083-970, Campinas, SP, Brazil.
Vijayalakshmi
Mookambesvaran
M
Todorova-Balvay
Daniele
D
Bueno
Sonia Maria Alves
SM
D000327:Adsorption; D002021:Buffers; D002614:Chelating Agents / Q000737:chemistry; D002846:Chromatography, Affinity / Q000295:instrumentation / Q000379:methods*; D005029:Ethylenediamines / Q000737:chemistry*; D006801:Humans; D007098:Imino Acids / Q000737:chemistry*; D007074:Immunoglobulin G / Q000302:isolation & purification*; D009532:Nickel / Q000737:chemistry*; D013696:Temperature
D002021:Buffers; D002614:Chelating Agents; D005029:Ethylenediamines; D007098:Imino Acids; D007074:Immunoglobulin G; C099539:tris(2-aminoethyl)amine; D009532:Nickel; C008109:iminodiacetic acid