Evaluation of guanidine-based multimodal anion exchangers for protein selectivity and orthogonality

Evaluation of preferred binding regions on ubiquitin and IgG1 FC for interacting with multimodal cation exchange resins using DEPC labeling/mass spectrometry

“…The selectivity in MM resins can be tuned by changing the binding conditions as shown by Robinson et al where the retention of IgG1 antibodies on MM resins was strongly impacted by the pH (Robinson, Roush, et al, 2018; Robinson et al, 2020). There is also a significant role of the ligand structure on MM interactions since the positioning of the charged and hydrophobic moieties in the ligands as well as the linker length can impact protein binding and create unique selectivity windows for protein separation (Koley et al, 2021; Robinson, Snyder, et al, 2018; Woo, Chen, et al, 2015; Woo, Parimal, et al, 2015). Woo et al carried out a detailed analysis of MM cation exchange (MM CEX) commercial and prototype resins using a model protein library and demonstrated the importance of ligand hydrophobicity and solvent exposure as well as the role of aromatic and aliphatic residue clusters on the protein surface (Woo, Parimal, et al, 2015) to protein retention behavior.…”

Protein adsorption and separation with monomodal and multimodal anion exchange chromatography resins. Part I. Multicomponent adsorption properties and frontal chromatography

“…While ring fluorination did not have a significant impact, protein retention generally increased with ligand hydrophobicity. More recently, Koley et al 8 compared the retention behaviors of the commercial resins Nuvia aPrime and Capto Adhere to those of resins with experimental multimodal ligands combining guanidine or bis-guanidine moieties with aromatic groups. Both guanidine and bis-guanidine ligands exhibited substantial increase in retention; however, protein recovery was limited, especially for the guanidine ligands.…”