Sterilizing Filtration Of Enriched And Pure Gaseous Oxygen Employed In Cell Culture ApplicationsSource: Pall Life Sciences - BioPharmaceuticals
Modern bioreactor aeration concepts increasingly using oxygen-enriched air or pure oxygen gas to improve cell culture productivity. As with air, these alternate oxygen source gas feeds must be filtersterilized to prevent spoilage of bioreactors by contaminant organisms coming from the incoming and outgoing gas streams. Membrane filters are used to sterilize these gases, and must also be integrity testable to assure process security and meet GMP requirements. The Water Intrusion Test has become a preferred choice for integrity testing of sterilizing grade gas filters due to its avoidance of alcohol as a test liquid. Exposing filters to pure oxygen streams, however, presents specific engineering challenges, because many materials such as organic matter, plastics or even metals can potentially ignite when in contact with oxygen, particularly if also subjected to static electrical discharges, high temperatures, pneumatic shocks or mechanical impact. For that reason several countries have established mandatory requirements or restrictions on use of these materials with gaseous oxygen or oxygen-enriched gases. Apart from these conditions, installations for gaseous oxygen including those using filtration need a dedicated risk assessment prior to use.