> For the complete documentation index, see [llms.txt](https://help.sbtinstruments.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.sbtinstruments.com/mpd/encyclopedia/get-starter-cultures/from-agar-plate-colony/determine-concentration.md).
# Determine concentration
The dispersed cells in the capture vial will be used to inoculate a liquid culture at a well-defined seeding concentration. To know which volume to add, first determine the cell concentration and then use the subcultivation calculator to determine the volume. The steps are demonstrated below.
{% stepper %}
{% step %}
**Prepare a 1:201 dilution**
Transfer 50 µL of your sample to 10 mL of diluent. Vortex 10 seconds at maximum speed.
{% endstep %}
{% step %}
**Measure on the diluted sample**
Transfer the tubing kit to the diluted sample.\
Press Measure and wait for the result to appear on the BactoBox® screen.
{% endstep %}
{% step %}
**Calculate cell concentration in capture vial**
Multiply the cells/mL with the dilution factor. In this case, it is 201
{% endstep %}
{% endstepper %}
## Summary
Now you know the cell concentration in the capture vial. Proceed to [Inoculate liquid culture](/mpd/encyclopedia/get-starter-cultures/from-agar-plate-colony/inoculate-liquid-culture.md) to calculate the volume of capture vial suspension needed to inoculate growth medium in the shake flask.
---
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