A T75 flask, also known as a T-75 or 75 cm² tissue culture flask, is a standard cell culture vessel used to grow and maintain adherent and suspension cells in vitro. The “T” stands for tissue culture, and the number “75” refers to the growth surface area of the flask, which is approximately 75 square centimeters.
T75 flasks are typically made of clear polystyrene plastic, which allows for easy visualization of the cells under a microscope. The interior surface of the flask is treated to promote cell adhesion and growth. T75 flasks have a rectangular shape, with a flat bottom and a vented or non-vented screw cap for airtight sealing. Vented caps contain a membrane filter that allows for gas exchange between the flask’s interior and the external environment while preventing contamination from microorganisms.
To culture cells in a T75 flask:
- Prepare the appropriate cell culture medium, typically containing a basal medium, supplements, and serum.
- Aspirate any remaining medium from the flask and wash the cells with sterile 1x phosphate-buffered saline (PBS) if needed.
- Add an appropriate volume of trypsin-EDTA to the flask to detach adherent cells. Incubate the flask at 37°C for 2-5 minutes, or until the cells have detached.
- Neutralize the trypsin with an equal volume of cell culture medium and gently resuspend the cells by pipetting.
- Transfer the cell suspension to a conical tube and centrifuge to pellet the cells.
- Aspirate the supernatant and resuspend the cell pellet in fresh cell culture medium.
- Count the cells and calculate the seeding density. Generally, 5-10 x 10^5 cells are seeded in a T75 flask, but the optimal seeding density may vary depending on the specific cell type.
- Add the appropriate volume of cell suspension to the T75 flask containing fresh culture medium, and mix gently to ensure even cell distribution.
- Incubate the flask in a humidified incubator at 37°C and 5% CO2. Monitor the cells daily for confluence, morphology, and contamination.
T75 flasks are widely used in research laboratories, biotechnology, and pharmaceutical industries for the growth and maintenance of various cell types, including primary cells, cell lines, and stem cells.
