Filtration is a separation and clarification technique used throughout biopharmaceutical manufacturing to remove particles, microorganisms, cell debris, or aggregates from a process stream based on size exclusion or charge interactions. Key filtration operations include depth filtration (clarification of harvest material), microfiltration (removal of cells and debris), ultrafiltration/diafiltration (UF/DF) (concentration and buffer exchange), and sterile filtration (0.2 µm bioburden reduction prior to fill and finish). Each filtration step must be carefully designed, scaled, and validated as part of the downstream process development workflow.
