Alternative antibody-binding affinity ligands are expected to support robust time-and cost-effective antibody purification with rapid improvement of upstream productivity and demand on downstream process optimization. Five new tetrapeptide biomimetic affinity ligands (FYRH, HWRH, YHRI, HYRF, and FHRA) were screened by modeling the molecular interaction mechanism between tetrapeptide ligands and the Fc fragment of IgG with molecular dynamics simulation and the flexible docking method, and the corresponding five resins were prepared in this work to evaluate their adsorption characteristics of human immunoglobulin G (hIgG). The results showed that the binding capacities to hIgG of the five resins showed a strong pHdependency, which was high at pH 7.0−9.0, and extremely low at pH 5.0−6.0, providing a benefit choice to separate hIgG. The dynamic binding capacities (DBC) at 10% breakthrough of five resins could reach up to 28−37 mg/mL gel , and Ac-FYRH-4FF resin showed the best adsorption performance. The elution test results with Ac-FYRH-4FF resin indicated that hIgG could be eluted mildly at pH 5.0 with a 96.5% recovery, meaning that this resin can be considered as a powerful candidate of alternative biomimetic affinity chromatographic resin.

Analytical characterization of a monoclonal antibody therapeutic reveals a three-light chain species that is efficiently removed using hydrophobic interaction chromatography, mAbs, 5:6, 925-935,

Short peptide biomimetic affinity chromatography as a novel antibody separation chromatography is a potential alternative to protein A chromatography. However, if directly attaching ligand to matrix, the adsorption capacity and mass transfer rate would be affected by pore blockage and steric effect. Grafting resin is an effective method to solve this problem by using polymer as a bridge between matrix and ligand. In this work, a novel resin was prepared by grafting a tetrapeptide to the dextran-grafted matrix. Then, the adsorption properties for human immunoglobin G and BSA were determined. The results showed the saturation adsorption capacity could reach to 133 mg/g resin at pH 8.9 with a significantly low dissociation constant (0.03 mg/mL). The influence of flow rates to dynamic binding capacity of this resin was less than that of the non-grafted resin. The separation performance of the resin showed monoclonal antibody could be well isolated from the Chinese hamster ovary culture supernatant at pH 9.0 with the purity of 93.0% and yield of 84.7% by one step. Overall, this resin could achieve higher binding capacity by the possible of gaining higher ligand density, indicating its potential significance for separation in larger scale systems.