Filters have been a part of bioprocessing since the beginning. Yet “broad optimization potential” still exists for established processes and in filter selection for new processes, according to Holger Bromm, marketing director for filtration technologies at Sartorius Stedim Biotech.
“Our product development in the last few years has focused on specific applications such as media and buffer prep, and filtration of downstream intermediates, which are core applications within bioprocesses.” Even within these categories filterability can differ significantly, for example, supplemented versus chemically defined media, or mAb product pools just before and just after capture/elute.
For these distinct applications, Sartorius Stedim has introduced the Sartopore® 2 XL product line, which is based on Sartopore 2 products but carries prefilter membranes optimized for specific applications. Two such products have been developed for media and downstream applications and one each for sterilizing-grade filtration and mycoplasma. To further optimize performance and reduce filtration cost per liter the company increased the effective filtration area by 30%.
As bioprocess streams become more complex, prefiltration becomes increasingly necessary. “Contaminants need to be removed reliably to protect more expensive sterilizing-grade and mycoplasma-retentive filters,” says Bromm. He notes that, while polyether sulfone (PES) membranes are now well accepted due to their excellent flow and throughput characteristics, PES has not been widely employed for prefiltration. Sartorius Stedim has addressed this deficiency through its Sartoguard PES membranes, which, according to Bromm, “transfer the benefits of PES membranes to prefiltration and help reduce costs further.”