Post cell culture or lysate clarification, involves a series of steps including gel purification, affinity chromatography, diafiltration, ultrafiltration and sterile filtration of final product concentrate.
Microfiltration applications in downstream processing includes:Buffer Filtration
Buffers required for equilibration, washing and elution during chromatography steps need to be filtered to prevent suspended particulate matter from blocking the chromatography matrix . The choice of filter pore size although normally depends on the bead size of the chromatography matrix, generally 0.45µm or 0.2 µm filters are used.
Sterilizing filtration of final product concentrates requires low protein binding, low hold up volume, validated 0.2 µm filters to minimize product losses.