Purification of monoclonal antibodies by chemical affinity mixed mode chromatography

The application of several pyridine-based compounds as immobilised ligands has been investigated for the purification of monoclonal antibodies via mixed mode chromatography. The ligands employed were 4′-terpyridinysulfanylethylamine (4′-TerPSEA), 5-bromo-2-pyridinylsulfanylethylamine (5-Br-2-PSEA), 2-quinolinylsulfanylethylamine (2-QSEA) and 4-pyridinylsulfanylethylamine (4-PSEA). The performance attributes of adsorbents, derived from the immobilisation of these different ligands onto Sepharose 6 Fast Flow™, was evaluated from batch adsorption studies and from chromatographic experiments with humanised IgG1, IgG2 and IgG4 monoclonal antibodies produced by stable CHO cell lines cultured in chemical defined media. These results demonstrated that monoclonal antibodies of different subclasses can be efficiently purified from crude CHO cell culture supernatants using these new chemical affinity chromatographic systems. Moreover, the majority of the CHO host proteins could be eliminated during the chromatographic purification step with these resins, as monitored by a specific ELISA assay.