Working with tip groups

Tip groups are logical groupings of tip racks that define how tips are used and managed during protocol execution. Understanding tip groups is handy for creating efficient protocols and managing tip usage effectively via the API.

Tip groups enable advanced features like tip reuse within a protocol, which can significantly reduce consumable costs and improve protocol efficiency.

About tip groups

A tip group is a named collection of one or more tip racks on the deck that share common usage patterns and behaviors within a protocol.

Tip groups are a specialized type of labware group specifically for tip racks.

Advantages of tip groups

Organize tip racks: Group related tip racks together for coordinated tip management.
Enable tip reuse: Configure whether tips should be reused between protocol steps.
Optimize tip usage: Reduce consumable costs by strategically reusing tips when appropriate.

Tip reuse behavior

The ReuseTipsBetweenSteps property controls tip reuse behavior.

When set to false (tip reuse disabled):

Tips are used for a single operation or step.
Each step that requires tips use fresh tips from the rack.
This is the safest option to prevent cross-contamination.

When set to true (tip reuse enabled):

Tips are re-racked after use, and they can be reused in subsequent steps of the same protocol.
Tips remain in use until explicitly discarded to waste.
When tips are discarded, the next available tips in the rack are used.
This reduces consumable costs, but it requires careful protocol design to avoid cross-contamination.

When tip reuse is enabled, verify that your protocol design prevents cross-contamination between incompatible samples or reagents.

Using tip groups in protocols

Defining tip groups in deck configuration

When creating a protocol via the API, tip groups are defined as part of the deck configuration. Each deck position containing a tip rack includes a labware group with tip-specific properties.

Example of a tip group in a deck position:

 {
  "position": 2,
  "positionName": "Tip Rack",
  "labwareGroup": {
   "groupName": "300uL Tips",
   "labwareId": 123,
   "reuseTipsBetweenSteps": false
  }
 }

Key properties:

groupName: A descriptive name for the tip group
labwareId: The ID of the tip rack labware
reuseTipsBetweenSteps: Boolean controlling tip reuse behavior

Refer to the LabwareGroupPostPutDto schema in the ML Prep OpenAPI documentation for details on labware group properties.

Referencing tip groups in protocol steps

Protocol steps reference tip groups by their ID. For example, in a Transfer Samples step, the tipLabwareGroupId field specifies which tip group to use for pipetting operations.

 {
  "tipLabwareGroupId": 5
 }

The tip group ID is assigned when the protocol is created and can be retrieved from the protocol's deck configuration.