Prepare an enzymatic assay

In this example, we will prepare an enzymatic reaction mixture using a Dragonfly dispenser, and then add cells manually. In this case, because we are using multiple execution devices, it is important to select the different components to be added in each stage of the workflow. To do so, we will use the element Make Mixtures, using the addition mode Liquid Selection, in combination with the element Mix Onto.

The mixture will contain:

Buffer (20% w/v)
Cells (10 ul)
Enzyme (15 nM)
Substrate (20 uM)
Water (as diluent)

In the workflow builder, define your mixture components using the Define Liquids and Plates element. For more information on how to use the Define Liquids and Plates, click here.
Add one element to your canvas: Make Mixtures.
Connect the Liquids parameter from the Define Liquids and Plates element to the Liquids To Make Mixtures input parameter of the Make Mixtures element.
Click on the Make Mixtures element to open the element parameter window. Here you can specify your mixtures. First, specify Parameters under Mixing Mode.
Now specify the composition of each mixture. To do so, give each mixture a name and add the names of the liquids defined in step 1.
Then specify which liquid should be used as a diluent. The diluent will only be used if the mixture composition is such that you need to top up with some volume to make the desired final volume or concentration. This can be specified globally for all mixtures or individually for each one.
Then, we specify the target volume for each mixture. In this case this is our final reaction volume of 250 ul.
Choose Liquid Selection under Addition Mode and then add all liquids, apart from Cells. Use “default” to apply the order to all mixtures.
Finally, specify how the number of replicates and how the mixtures should be laid on a plate. Select Let Synthace Optimise from the dropdown menu for Layout and Replicate Grouping.
Define a Plate Set Name. This can be any alphanumeric name such as Mixtures
Select a Plate Type from your plate library. Take care to ensure the plate type you select can accommodate the final volume for your mixtures.
Add a new stage to your workflow by clicking on the + button.
Add one element to your canvas: Mix Onto and ensure it is in Stage 2.
Connect the Remaining Transfers parameter from Make Mixtures to the Transfers to Complete input parameter of the Mix Onto element. Repeat for Mixtures to Destination Liquids and Remaining Liquids to Mix to Source Liquids.
Choose Liquid Selection under Addition Mode, this time only selecting Cells.
Note: if you don't select an addition mode at all, this Mix Onto element will simply add all remaining liquids, as defined in the mixture composition in Make Mixtures.