BioOptimal™ MF-SL can produce a high quality filtrate even from a feed solution with low cell viability and high turbidity. The figure on right compares the turbidities of a filtrate produced by BioOptimal™ MF-SL and a filtrate produced by a competitor filter, both using feed solutions of CHO cells with cell densities of 1.48×107 cells/mL, viabilities of 78.6%, and turbidities of 1600 NTU. The BioOptimal™ MF-SL filtrate clearly shows a much higher degree of clarity.
The very low filtrate turbidity provided by BioOptimal™ MF-SL contributes to the improvement of the subsequent purification steps in the downstream process. As figure on right shows, the filtration capacity of a 0.22 µm sterile filter is much less affected by the BioOptimal™ MF-SL filtrate than the Microfilter A (flat sheet membrane) filtrate.
BioOptimal™ MF-SL’s tangential flow filtration mode allows it to cause little cell damage during filtration, thus reducing the release of impurities caused by cell disruptions to a minimum. The figure on right shows the amounts of lactate dehydrogenase (LDH), a cell disruption-derived impurity, in the filtrates produced by BioOptimal™ MF-SL and by two traditional depth filters. It is easy to see that BioOptimal™ MF-SL causes less cell damage.
BioOptimal™ MF-SL is able to clarify solutions quickly and completely in a single processing step. Therefore, it simplifies the cell culture clarification process and makes it more cost-effective by eliminating the needs for large investments like centrifuges and expensive disposable items like other depth filters.