Sterilization of filtration units
Sterilization of filtration units
This lab was derived from: Animal Cell Culture - A Guide to Basic Techniques (5th Edition)
Operation method
Programme 11.4 Sterilization of filtration units
Materials and Instruments
Filter Housings Shelves Prefilters Fiberglass Nylon Bags Autoclave Sterility Indicator Tape Sterilization Kettles Move 1. After a thorough cleaning with detergent, rinse the filter unit with water, then with deionized water and allow to air dry. Caveat 1. Selection of sterilization methodsMany plastic utensils cannot be autoclaved or dry heat sterilized because the temperature is too high. When sterilizing these vessels, soak them in 70% ethanol for 30 minutes, then place them in a laminar flow hood and dry them under ultraviolet light. Particular care should be taken with some plasticware (e.g., Plexiglas, plastic glass, clear synthetic resins) because they will depolymerize in ethanol or when exposed to UV light. Vinyl oxide can be used to sterilize plasticware, but it takes two to three weeks after sterilization to wash it all off the plastic surface. The best method of sterilizing plasticware is y-irradiation, standardized to 25 kGy. Ware should be packaged and sealed in polyethylene plastic with a heat-welded closure. For more product details, please visit Aladdin Scientific website.
2. Insert a filter plate into the filter and place the filter membrane onto the plate, wetting it to eliminate static electricity if the membrane is made of polycarbonate.
3. place the pre-filter (fiberglass and other desired substances) on top of the filter.
4 . Install the filter bracket, do not tighten completely (you can leave a screw ring).
5. seal the inlet and outlet of the filter with aluminum foil.
6. Wrap the filter unit in sterilized paper or steam-permeable nylon film and apply sterile indicator tape.
7. High-pressure sterilize the filter at 121°C, 100 kPa (1 bar, 15 lb/in2 ) for 20 min without the pre-vacuum and post-vacuum cycles (when using an automatic autoclave, use the "Liquid Cycle" procedure).
8. Remove the filter and cool it.
9. Do not tighten the filter holder completely until filtration has begun and the membrane is already wet.