(53g) Effect of Freeze-Thaw, Protein Concentration, and pH on Antibody Aggregation in Bioprocess Protein a Chromatography

Therapeutic proteins such as monoclonal antibodies are commonly subjected to freeze-thawing for analytical testing, shipping, and storage. Freeze-thawing stress can potentially expose protein molecules to the ice-liquid interface and induce protein aggregation. We studied the effects of freeze-thawing on aggregation of an IgG₂ monoclonal antibody, specifically after Protein A purification. Several solution conditions including pH and protein concentration were found to significantly impact aggregation of the antibody during freeze-thawing. Based on these findings, the proposed mitigation strategy aims to minimize freeze-thaw related aggregation during small-scale process development, analytical testing, and manufacturing.