Cell Culture Dishes Frequently Asked Questions
1. How many cells should I seed to start a cell culture?
As cells proliferate after seeding, it is not recommended to seed cells in such a way that the average yield per well is exceeded at 100% confluence. Dependent on the cell type, cell size and cell growth rate, and the number of days of your experiment you may start your cell culture with different seeding densities. Below are the recommended seeding densities in different cell culture dishes. The number of cells on a confluent plate or dish varies dependent on the cell type. HeLa cells were used for the table. The optimal cell inputs for your specific cell lines can be determined by initial growing tests.
Dishes | Surface Area (cm2) | Seeding Density | Cells at Confluency |
|---|---|---|---|
35mm | 8.8 | 0.3 x 106 | 1.2 x 106 |
60mm | 21.5 | 0.8 x 106 | 3.2 x 106 |
100mm | 56.7 | 2.2 x 106 | 8.8 x 106 |
150mm | 145 | 5.0 x 106 | 20.0 x 106 |
Plates | Surface Area (cm2) | Seeding Density | Cells at Confluency |
|---|---|---|---|
6-well | 9.6 | 0.3 x 106 | 1.2 x 106 |
12-well | 3.5 | 0.1 x 106 | 0.5 x 106 |
24-well | 1.9 | 0.05 x 106 | 0.24 x 106 |
48-well | 1.1 | 0.03 x 106 | 0.12 x 106 |
96-well | 0.32 | 0.01 x 106 | 0.04 x 106 |
2. How can I choose the right growth surface for my cell cultures?
Optically clear and non-treated polystyrene with a hydrophobic surface is ideal for suspension cell culture. It is also useful for a variety of biochemical assays. A standard tissue culture (TC) surface modification makes the polystyrene surface more hydrophilic and allows maximum adhesion for a wide range of cell types. For cells such as primary cells and sensitive cells that do not grow well on the normal TC surface, you can use cell culture dishes coated with collagen or poly-lysine. Collagen is of animal origin, while poly-lysine is fully synthetic.
3. Do cell culture plates and dishes have an expiration date?
Yes, they do. The expiration date usually refers to guaranteed sterility. It should of course be noted that sterility is also dependant on proper handling ensuring the packaging remains intact. Some culture vessels have added substances such as gelatin that can degrade over time. It is not recommended to use these types of cell culture vessels after the expiration date.