Protocol Editor: The Pipettes (Part 3 of 4)

Physical Setup

An OT-One will hold up to two pipettes. A single channel pipette can be used on the left side (axis B), or the right side (axis A), but a multi channel will only fit on axis A.


If you consider all the different things you can do with a pipette by hand ... the list in your head probably isn’t that long. But there are so many variables to consider when programming a pipette, and the OT-One gives you the ability to control all of them. Here we'll give a run-down of the various elements and variables you can manipulate by using the OT-One.

Left side: filled-out parameters. Right side: default parameters.

  • Name

Simply: what you want to name your pipette. Like the deck containers, this name will be used throughout the protocol, so make it something easy to type!

  • tool

This will always be “pipette”. Long-term OpenTrons goals include being able to use a variety of lab equipment, but for now we’re just focusing on pipettes.

  • tip-racks

This is where you assign a tip rack to each pipette. The tip rack must exist in the deck to be called here, and the names of each must match.

  • trash-container

As the trash container must be named “trash”, this attribute will always be the same.

  • multi-channel

A pipette is either a multi channel (True), or single channel (False).

  • axis

This is where you tell the robot which pipette is on the right (a), and which is on the left (b).

  • volume

The volume is the maximum volume of the pipette: 10 for a 10 uL pipette, 200 for a 200 uL, and so on. Even if you use less than the maximum volume in your experiment, this needs to be set to the maximum.

  • down-plunger-speed

How fast the plunger is depressed is defaulted to 300, but can be adjusted up or down.

  • up-plunger-speed

How fast the plunger is released is defaulted to 500, but, like the down-plunger-speed, it can be adjusted.

  • tip-plunge

This distance is how far the pipette drops when it is instructed to pick up a tip, and should be set to 6.

  • extra-pull-volume

If you want the robot to pull up more liquid than is set in each transfer, you can specify that extra volume here.

  • extra-pull-delay

Once a volume has been specified for extra-pull-volume, you can tell the robot to delay for a specific amount of time before pulling up the extra volume. Like the “delay” attribute, this is in seconds. If the extra-pull-volume is 0, there will not be a delay.

  • distribute-percentage

For use with the distribute command, extra volume will be drawn up at the start of the command.

See also: Creating a Protocol (Part 1), The Deck (Part 2), and The Instructions (Part 4).