# 1:100 dilutions

For every 30 minutes, collect a fresh sample and repeat the procedure from the 1:100 dilution. 

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## <i class="fa-spray-can">:spray-can:</i> Do a *Clean* program after each measurement.&#x20;

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## <i class="fa-hourglass">:hourglass:</i> Start a 30-minute countdown to remind you to collect the next sample.

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### Prepare the sample for BactoBox® measurement

1. Use a serological pipette to transfer a sample from the shake flask to a vial.
2. Use a permanent marker to label the vial cap with the sampling time.
3. Start a 30-minute countdown to remind you to collect the next sample.&#x20;
4. Vortex 30 seconds at max speed to disaggregate bacteria.
5. Make a 1:100 dilution:
   1. Transfer 101 µL of your sample to 10 mL of diluent.&#x20;
   2. Vortex 10 seconds at max speed.
6. Transfer the tubing kit to the diluted sample.

<figure><img src="https://4216107837-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FeYTtd7c0A325muFr5lMW%2Fuploads%2Fyvo1ZGsZ65GFtFu9wnMc%2FT0_prepare.avif?alt=media&#x26;token=297976a5-374a-41b6-91e9-bd92085521c7" alt=""><figcaption></figcaption></figure>
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{% step %}

### Measure the diluted sample on BactoBox®

1. Click the  <kbd><mark style="background-color:purple;">Measure<mark style="background-color:purple;"></kbd> button in Access.&#x20;
2. Add metadata:&#x20;
   1. Dilution: <kbd>100</kbd>.
   2. Label: <kbd>E\_coli\_growth</kbd>.&#x20;

<figure><img src="https://4216107837-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FeYTtd7c0A325muFr5lMW%2Fuploads%2FQlTbM3N8hw1fFLPgH6jr%2FLag_measure.avif?alt=media&#x26;token=ff68d20a-3e34-437d-9d11-e5854b099be8" alt=""><figcaption></figcaption></figure>
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### Clean the device

1. Transfer the tubing kit to the disinfection vial.
2. Click <kbd>Clean</kbd>.&#x20;
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## Summary

The 1:100 dilution scheme works well for the measurements during lag and early-exponential growth stage. As the concentration increases, you'll need to dilute more. We will explain this in detail in the next section.&#x20;