Liquid Handling - Single Channel

Single channel liquid handling at Strateos will be done via an air displacement syringe pump-based liquid handling robot.

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Design Considerations

Liquid handling is a deceptively complex process and there are many details that must be considered during protocol design in order to achieve high levels of reliability and precision. Be sure to review the Design Rules & Limitations section of this document in depth.

Instruction and Parameters

{
  "op": "pipette",
  "groups": [group]
}

Where "group" is one of:

Transfer

{ "transfer": [ {
  "from": well,
  "to": well,
  "volume": volume,

  // optionally:
  "aspirate_speed": flowrate,
  "dispense_speed": flowrate,
  "mix_after": {
    "volume": volume,
    "speed": flowrate,
    "repetitions": integer
  },
  "mix_before": {
    "volume": volume,
    "speed": flowrate,
    "repetitions": integer
  }
  } ]
}

transfer operations will move liquid from a single well to a single well. This operation can work on tubes and plates and is often executed on a single-channel Tecan Omni. Every transfer uses a new tip, unless the transfers are specified within the same transfer group.

Volume Range%CV (Coefficient of Variation)
<5μL3%
5μL - 200μL5%
200μL - 1000μL1% or less

Aspirate, Dispense and Mix Speeds

ParameterMinimumMaximumDefault
aspirate_speed2.5uL/sec1000uL/secFor <=2uL, 50uL/sec
For <=5uL, 100uL/sec
For >5uL, 300uL/sec
dispense_speed2.5uL/sec1000uL/secFor <=2uL, 50uL/sec
For <=5uL, 100uL/sec
For >5uL, 300uL/sec
mix_speed2.5uL/sec1000uL/sec100uL/sec

Distribute

{ "distribute": {
    "from": well,
    "to": [ {
      "well": well,
      "volume": volume,

      // optionally:
      "dispense_speed": flowrate
    } ],

    // optionally:
    "allow_carryover": boolean, // defaults to false 
    "aspirate_speed": flowrate,
    "mix_before": {
      "volume": volume,
      "speed": flowrate,
      "repetitions": integer
     }
   } 
}

distribute operations require one from well and many to wells. This instruction uses a single tip and this tip will touch the liquid in each of its destination wells when dispensing due to automatic liquid level sensing. If the Tecan cannot aspirate enough liquid to distribute the specified volume to all wells in a group, it will discard the tip and use a new one to continue the operation. To allow the pipette to return to the source well and aspirate additional liquid using the same tip, set allow_carryover to true.

Volumes below 5μL cannot be distributed and should be transfered using the same tip.

In addition to the nominal volume you wish to pipette, this instruction requires an additional disposal volume to be available.

For accurate pipetting, we use the following disposal volumes:

Volume RangeDistribute CapabilityDistribute Disposal Volume
<10μLNo, you should use transfer.
10μL - 40μLYes10μL
40μL - 200μLYes25% of distribute volume
200μL - 1000μLYes

Consolidate

{ 
  "consolidate": {
    "to": well,
    "from": [ {
      "well": well,
      "volume": volume,

      // optionally:
      "aspirate_speed": flowrate
    } ],

    // optionally:
    "dispense_speed": flowrate,
    "mix_after": {
      "volume": volume,
      "speed": flowrate,
      "repetitions": integer
    }
	} 
}

consolidate operations require many from wells and one to well. It will always be executed on a single-channel Tecan Omni. The same tip is used for all operations.

Mix

{ 
  "mix": [ 
    {
    "well": well,
    "volume": volume,
    "speed": flowrate,
    "repetitions": integer
		},
  ] 
}

A mix operation is a single well pipetting operation. It is executed on a single-channel or a 96-channel according to the same rules as described for transfer. Speed is limited to 2.5-1000:microliter/second for Single Channel Liquid Handling and 0.1-500:microliter/second for Multichannel Liquid Handling (Stamping).

Tips

The tips used for pipetting are automatically selected based on the total volume being moved in a single operation. This total volume may consist of actual volume, disposal volume and dead volume depending of the pipetting operation as described above.

Tip sizeMaximum volume to be pipettedMinimum volume to be pipetted
Small38μL1μL
Large750μL30μL