Advance chromatin extraction improves the performance of electropositive mixed-mode chromatography as a capture step and enables its integration with void-exclusion anion exchange chromatography as a two-column-step purification platform for monoclonal antibody production

•Electropositive mixed-mode chromatography was primary step for IgG purification.•Advance chromatin extraction improves electropositive for antibody binding.•Salt modulated IgG retention on electropositive mixed-mode chromatography.•VEAX was integrated with electropositive mixed-mode chromatography.•A two-column-step purification without protein A chromatography was established.