Monoclonal Antibody Purification with Reduced Turbidity by using High-salt Elution Buffer During Protein a Chromatography

Abstract

During purification of monoclonal antibodies, viral inactivation/removal step is a mandatory step to comply with the regulatory guidelines which commonly performs at low pH about 3.5 and further neutralizes it to a pH about 7.0. Neutralization of monoclonal antibodies results formation of high turbidity which is troublesome for further processing such as filtration and other chromatography processes and it eventually leads to filter clogging and increases column back pressure. In this work, we propose a new optimized process of affinity chromatography (Protein A) by using a high salt elution buffer which reduces turbidity more than 80%. A systematic study of different concentration of salts were analysed and it reveals that salt concentration greater than 100mM in Protein A elution buffer reduces turbidity during neutralization of monoclonal antibodies when compared to low salt concentration of elution buffer. We also found that elution of monoclonal antibodies during Protein A chromatography at pH 3.5 results higher reduction of turbidity compared to pH 3.0. These findings provide both cost and time effective for large scale production of monoclonal antibodies as it eliminates the use of multiple filters throughout the purification process.