Silk screen based dual spin-filter module for perfusion culture of adherent and non-adherent mammalian cells

Spin-filters have been primarily used for producing therapeutic proteins from mammalian cells. However, disposability and/or high filter clogging of the existing spin-filter systems affect the process economy and productivity. Hence, to address these drawbacks a reusable dual spin-filter module for perfusion culture of adherent and non-adherent mammalian cells was designed. Two non-woven Bombyx mori silk layers were used as filter screen; the outer layer was conducive to cell attachment whilst the inner was non-conducive. Adherent cells can be cultured either in suspended mode using its inner single module or as monolayer of cells using its dual concentric module. We achieved 30 % higher urokinase productivity as compared to the stainless-steel spin-filter during perfusion experiments of adherent human kidney cells in suspended mode. This was due to the hydrophobic and negatively-charged silk screen that allows clog-free perfusion culture for prolonged periods.