Removal of polysorbates degradation-related impurities by depth filter screening: A case study

Depth filtration (DF) is widely utilized as a clarification step in pharmaceutical manufacturing, concurrently removing process-related impurities such as host cell proteins (HCPs) and DNA. This study demonstrates DF's capability in eliminating polysorbates (PS)-degrading impurities (esterases and metals) that may compromise the long-term stability of biopharmaceuticals. By using mass spectrometry-based methods, screening experiments with various commercial depth filters revealed significant brand-dependent variations in impurity removal efficiency. Our findings provide valuable reference data for projects requiring HCP removal, particularly those targeting challenging esterase or metals contaminants.