|Comparison of protein recovery from various centrifugal filters. The recovery of a 25 kDa protein (α-chymotrypsinogen A) solution (4 mL of 1 mg/mL in PBS, pH 7.4) was evaluated using two different 10 kDa centrifugal filters. Filters were centrifuged in a fixed angle rotor, at 7,500 x g, for 30, 20 and 15 minutes, respectively, as recommended by the manufacturers. It was expected that the 25 kDa protein would be retained by both 10 kDa filters.
|Comparison of extractable impurities from two centrifugal filters as detected by LC-UV. Samples of Milli-Q® water were spun for 30 minutes at 2,000 x g. Filtrate (1 mL) was taken for analysis by LC-UV.