Hi.
One possibility is to use a series of filters of different porosities, the
first being one with a large pore diameter (equal to or even greater than 0.8
micron) coupled with a prefilter. These filters could be premoistened by
passing a small volume of cell culture medium through them (which is then
discarded), and then pass the serum through it. Then take the
resulting filtrate and pass it through smaller filter (0.45 or 0.22 micron
without a prefilter). Good luck.
KW Theil
Wooster, Ohio
