> 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/mini-course/screen-growth-media.md).

# Screen growth media

This is the [Screen growth media workflow](/mpd/workflows/best-medium.md) summarized to key steps. You measure the same strain grown in different media and pick the one that reaches the highest cell concentration.

<figure><img src="/files/JqHhWWJoiemGESGmuBaK" alt=""><figcaption><p>Where you end up: the growth medium with the highest cells/mL wins.</p></figcaption></figure>

***

{% stepper %}
{% step %}

### Grow the media you want to compare

Inoculate at least two growth media with the same starter culture, about 24 hours ahead, so every culture sits in its stable plateau at the first measurement.

<figure><img src="/files/VZLXcKT7dHCecpOA5Fxp" alt=""><figcaption><p>Same starter culture, different media.</p></figcaption></figure>
{% endstep %}

{% step %}

### Create a measurement group

Open Access and create a *basic* measurement group so every reading lands in the same place.

<figure><img src="/files/QCcFnsvDUxI5alqhS53v" alt=""><figcaption><p>Plug in your BactoBox® and open Access.</p></figcaption></figure>
{% endstep %}

{% step %}

### Measure each medium

Sample 1 mL, vortex 1 minute, dilute 1:100 then 1:10,000, and measure. Label each reading with the medium (for example `LB` or `TSB`) and set the dilution to 10,000. Repeat for every medium, at three time points across the plateau.

<figure><img src="/files/f9kAUrtMfXrTeJLjgKmb" alt=""><figcaption><p>A 1:10,000 dilution lands the dense culture in range.</p></figcaption></figure>
{% endstep %}

{% step %}

### Identify the best medium

Export the data, average the three time points per medium, and compare. The highest mean cells/mL is the best medium.

<figure><img src="/files/JqHhWWJoiemGESGmuBaK" alt=""><figcaption><p>Terrific broth reaches the highest cell concentration here.</p></figcaption></figure>
{% endstep %}
{% endstepper %}

***

## Do it yourself

That is the whole loop. The full workflow covers the sampling schedule, the dilution steps, and the data analysis, step by step.

{% content-ref url="/pages/LQH8L6gm4m1NETVVaulL" %}
[Screen growth media](/mpd/workflows/best-medium.md)
{% endcontent-ref %}


---

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