What is cell doubling time?
Cell doubling time is the amount of time it takes for a given population of cells to double in number. It is a critical metric in mammalian cell culture, tissue engineering, and microbiology to monitor the health and growth kinetics of cell lines.
How to calculate doubling time
To compute the doubling time of your cell culture, you need to know three pieces of information:
- Initial Cell Count: The number of cells initially seeded.
- Final Cell Count: The number of cells counted at the time of harvesting or passaging.
- Time Elapsed: The duration between the initial and final counts, typically measured in hours.
Formula for doubling time
Assuming the cells are growing in the exponential (log) phase, you can calculate the doubling time using the following formula:
DT = t * ln(2) / ln(Nf / Ni)
Where:
- DT = Doubling Time
- t = Time elapsed
- Nf = Final cell number
- Ni = Initial cell number
- ln = Natural logarithm
Additionally, you can determine the specific growth rate (μ) as μ = ln(Nf / Ni) / t, and the number of population doublings (PD) as PD = ln(Nf / Ni) / ln(2).