Typically 1:4 to 1:20 dilutions are appropriate for most cell lines. b. Adherent cells. Horizontal hoods are designed such that the air flows directly at the operator hence they are not useful for working with hazardous organisms but are the best protection for your cultures. Proteolytic enzymes — Trypsin, collagenase, or pronase, usually in combination with EDTA, causes cells to detach from the growth surface. This design can be configured as individual controllers/starters or in control center lineups with incoming disconnect switches or in conjunction (bussed) with our HVK switchgear. Use prewarmed media and have cells out of the incubator for as little time as possible.
The dilution you use will depend on the density of the cells and how quickly they divide, which only you can determine. They should not be vortexed, vigorously pipetted or centrifuged at greater than 1500 g. 3. Cell feeding. About every 2-3 days, dilute the cells into fresh media. Live cells are phase bright; suspension cells are typically rounded and somewhat symmetrical; adherent cells will form projections when they attach to the growth surface. Before using the microscope or whenever an objective is changed, check that the phase rings are aligned. D. Preservation.
Ideally, cells are harvested when they are in a semi-confluent state and are still in log phase. The most convenient vessels are specially-treated polystyrene plastic that are supplied sterile and are disposable. Tissue Culture Methods I. TYPES OF CELLS GROWN IN CULTURE Tissue culture is often a generic term that refers to both organ culture and cell culture and the terms are often used interchangeably. Adherent cultures that do not need to be divided can simply be fed by removing the old medium and replacing it with fresh medium. The vertical hood, also known as a biology safety cabinet, is best for working with hazardous organisms since the aerosols that are generated in the hood are filtered out before they are released into the surrounding environment. Cells do not typically like to be too confluent so they should be subcultured when they are in a semi-confluent state. In general, mammalian cells should be handled gently.