# Dilute 1:100 000

In the example below, the end-user had a concentrated fermentation that resulted in a concentrated end-product. This required a 1:100 000 dilution of the end product before the BactoBox® measurement. 

The end-product is viscous and therefore slightly difficult to pipette reliably with a P200 pipette. To get around this, we start with a 1:10 dilution followed by two sequential 1:100 dilutions (10 × 100 × 100 = 100,000). Once mixed together, we call it your *sample vial* from now on.

![Serial dilution for making a 1:100,000 dilution](https://4216107837-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FeYTtd7c0A325muFr5lMW%2Fuploads%2FEHcClF4tfdce7Qc7oEpl%2F6.png?alt=media)

Once you get the hang of the screening procedure, it is snappy to do the dilutions.

Viscous liquid can be difficult to pipette accurately. If this is the case, use a weight to help you. Place the 9 mL of sample on the weight and use the weight as guide while you pipette the sample into the vial.

{% hint style="success" %}

## Vortex each dilution step thoroughly!

Always vortex thoroughly for at least **10 seconds**. Ensure that a clear cyclone/vortex appears.

You must perform proper vortexing to ensure that the transferred bacteria are well-mixed in the prepared dilution. Without proper vortexing, you may get underestimation of concentration and variation between replicates.
{% endhint %}

{% hint style="warning" %}

## Your sample vial is for *single use* only

Once you run the liquid through BactoBox®, the properties change *significantly*.

**Always discard your sample vial after use!**
{% endhint %}