This article covers best practice methods for:
Pipette attachment best practices
It is important to be mindful during pipette attachment, so that the position of the pipette relative to the mount is consistent each time a pipette is removed and reattached.
The variability can be significantly limited if all three screws attaching the pipette to the mount are properly screwed in.
Multi-channel pipettes are especially sensitive to tilt. When attaching them, some extra care is needed to make sure they are perfectly straight.
Tip attachment best practices
Variability in the position of the tip relative to the pipette is another common root cause of calibration or movement issues in Gen1 pipettes. Use the following method to avoid issues during calibration and protocols.
Visual check of tip position
There are two calibration processes that require manual tip attachment: deck calibration and pipette calibration. To get the most ideal tip position for these processes, simply do a visual check from the front and side to ensure the tip is pointing straight down, not at an angle.
Deck calibration best practices
You must calibrate the deck using Opentrons/GEB tips that we supply. If you use a third party tip for deck calibration, your deck calibration data will be corrupt.
Any of our pipettes can be used to complete deck calibration, but some pipettes are better than others for completing deck calibration.
For best results, use one of the following pipettes: P300 single channel, P50 single channel, P20 single channel, or P10 single channel.
If you do not have any of these pipettes, or if you do not have Opentrons/GEB tips for any of these pipettes, then use any of the other pipettes you have in your possession (assuming you have the matching Opentrons/GEB tips).
Pipette calibration best practices
For optimal behavior during calibration, follow these guidelines:
Make sure you've only assigned one type of tip for any one pipette in your protocol. Meaning: if you are using 300ul Opentrons/GEB tips for your P300 single channel pipette, do not assign 300ul TipOne tips to the same pipette in the same protocol. The robot can only store data for one type of tip for any pipette at a time.
During pipette calibration, make sure the tip you are attaching to the pipette is the same type of tip you have assigned for that pipette in your protocol.
Cancelling pipette calibration
There is no method in the app currently to cancel pipette calibration once it's started. This can be a problem if there is corrupt data stored on the robot, or if the wrong tip has been attached, as it can cause the robot to crash against the fixed trash or tip probe switches.
To prevent this, it is a best practice to keep your finger ready on the robot's power switch to power the robot off during pipette calibration if a crash is about to happen. If you experience crashing and are concerned your robot or pipette has been damaged, please contact technical support.
Labware calibration best practices
For best results, we recommend using pre-loaded labware definitions and labware. For more information, refer to the following article: What Labware can I Use with the OT-2?
Checking labware/definition match
Ensure that the labware loaded in the protocol matches the labware you're placing on the deck for your run. Learn how to do this using our labware library in the following article: Using the Labware Library.
Determining that the tip is centered over and even with the top of well A1 can be tricky. Take care in doing so and use the following guidelines to check the position thoroughly if you are able:
Crouch so that your eyes are level with the top of the labware
Do a visual check from the front and the side
When doing the visual check, close one eye and position yourself so that your open eye is lined up with a column or row of wells. You have reached the right position to check from when the column or row of wells appears as one line when checking from the front or side.