2.2.4. Higher spike X-MuLV on Planova BioEX and S20N filters
To conduct viral clearance with a higher load titer of X-MuLV, 10 mg/mL mAB spiked with 2% X-MuLV (0.2 μm prefiltered) was filtered on 0.0003 m2 Planova BioEX and 0.001 m2 S20N filters with a load volume of 300 and 1000 mL, respectively, corresponding to a throughput of 1000 L/m2, and a flow rate of 0.2 and 0.667 mL/min, respectively, corresponding to a flux of 40 LMH for each filter (Table 4). The spike solution was loaded to the filter using the sample pump of AKTA pure 25. The log titer of load solution in this test is effectively higher than the inline spike test described previously because of higher spike concentration.