Evaluation of Iminodiacetic Acid (IDA) as an Ionogenic Group for Adsorption of IgG1 Monoclonal Antibodies by Membrane Chromatography

Iminodiacetic acid (IDA) is one of the chelating ligands most frequently employed in immobilized metal-ion affinity chromatography (IMAC) due to its ability to act as electron-pair donor, forming stable complexes with intermediate and borderline Lewis metal ions (electron acceptor). Thus, IDA can also be employed in ion exchange chromatography to purify positively charged proteins at neutral pH values. This study aimed to evaluate IDA as an ionogenic group (ion exchanger) immobilized on poly (ethylene vinyl alcohol) (PEVA) hollow fiber membranes for immunoglobulin G₁ (IgG₁) monoclonal antibody (MAb) purification. IDA-PEVA membranes showed considerable promise for MAb purification, since IgG₁ was recovered in eluted fractions with traces of contaminants as confirmed by Western blotting and ELISA analysis. Quantification of IgG₁ showed that a purity of 94.2% was reached in the elution step. Breakthrough curve and batch adsorption experiments showed that the MAb dynamic binding capacity (DBC) of 3.10 mg g^-1 and the maximum adsorption capacity of 70 mg g^-1 were of the same order of magnitude as those found in the literature. The results obtained showed that the IDA-PEVA hollow fiber membrane could be a powerful adsorbent for integrating large-scale processes for purification of MAb from cell culture supernatant.