Opentrons Integration

Every Opentrons protocol follows a standard structure:

from opentrons import protocol_api

# Metadata
metadata = {
    'protocolName': 'My Protocol',
    'author': 'Name <[email protected]>',
    'description': 'Protocol description',
    'apiLevel': '2.19'  # Use latest available API version
}

# Requirements (optional)
requirements = {
    'robotType': 'Flex',  # or 'OT-2'
    'apiLevel': '2.19'
}

# Run function
def run(protocol: protocol_api.ProtocolContext):
    # Protocol commands go here
    pass

Key elements:

• Import protocol_api from opentrons
• Define metadata dict with protocolName, author, description, apiLevel
• Optional requirements dict for robot type and API version
• Implement run() function receiving ProtocolContext as parameter
• All protocol logic goes inside the run() function

2. Loading Hardware

Loading Instruments (Pipettes):

def run(protocol: protocol_api.ProtocolContext):
    # Load pipette on specific mount
    left_pipette = protocol.load_instrument(
        'p1000_single_flex',  # Instrument name
        'left',               # Mount: 'left' or 'right'
        tip_racks=[tip_rack]  # List of tip rack labware objects
    )

Common pipette names:

• Flex: p50_single_flex, p1000_single_flex, p50_multi_flex, p1000_multi_flex
• OT-2: p20_single_gen2, p300_single_gen2, p1000_single_gen2, p20_multi_gen2, p300_multi_gen2

Loading Labware:

# Load labware directly on deck
plate = protocol.load_labware(
    'corning_96_wellplate_360ul_flat',  # Labware API name
    'D1',                                # Deck slot (Flex: A1-D3, OT-2: 1-11)
    label='Sample Plate'                 # Optional display label
)

# Load tip rack
tip_rack = protocol.load_labware('opentrons_flex_96_tiprack_1000ul', 'C1')

# Load labware on adapter
adapter = protocol.load_adapter('opentrons_flex_96_tiprack_adapter', 'B1')
tips = adapter.load_labware('opentrons_flex_96_tiprack_200ul')

Loading Modules:

# Temperature module
temp_module = protocol.load_module('temperature module gen2', 'D3')
temp_plate = temp_module.load_labware('corning_96_wellplate_360ul_flat')

# Magnetic module
mag_module = protocol.load_module('magnetic module gen2', 'C2')
mag_plate = mag_module.load_labware('nest_96_wellplate_100ul_pcr_full_skirt')

# Heater-Shaker module
hs_module = protocol.load_module('heaterShakerModuleV1', 'D1')
hs_plate = hs_module.load_labware('corning_96_wellplate_360ul_flat')

# Thermocycler module (takes up specific slots automatically)
tc_module = protocol.load_module('thermocyclerModuleV2')
tc_plate = tc_module.load_labware('nest_96_wellplate_100ul_pcr_full_skirt')

3. Liquid Handling Operations

Basic Operations:

# Pick up tip
pipette.pick_up_tip()

# Aspirate (draw liquid in)
pipette.aspirate(
    volume=100,           # Volume in µL
    location=source['A1'] # Well or location object
)

# Dispense (expel liquid)
pipette.dispense(
    volume=100,
    location=dest['B1']
)

# Drop tip
pipette.drop_tip()

# Return tip to rack
pipette.return_tip()

Complex Operations:

# Transfer (combines pick_up, aspirate, dispense, drop_tip)
pipette.transfer(
    volume=100,
    source=source_plate['A1'],
    dest=dest_plate['B1'],
    new_tip='always'  # 'always', 'once', or 'never'
)

# Distribute (one source to multiple destinations)
pipette.distribute(
    volume=50,
    source=reservoir['A1'],
    dest=[plate['A1'], plate['A2'], plate['A3']],
    new_tip='once'
)

# Consolidate (multiple sources to one destination)
pipette.consolidate(
    volume=50,
    source=[plate['A1'], plate['A2'], plate['A3']],
    dest=reservoir['A1'],
    new_tip='once'
)

Advanced Techniques:

# Mix (aspirate and dispense in same location)
pipette.mix(
    repetitions=3,
    volume=50,
    location=plate['A1']
)

# Air gap (prevent dripping)
pipette.aspirate(100, source['A1'])
pipette.air_gap(20)  # 20µL air gap
pipette.dispense(120, dest['A1'])

# Blow out (expel remaining liquid)
pipette.blow_out(location=dest['A1'].top())

# Touch tip (remove droplets on tip exterior)
pipette.touch_tip(location=plate['A1'])

Flow Rate Control:

# Set flow rates (µL/s)
pipette.flow_rate.aspirate = 150
pipette.flow_rate.dispense = 300
pipette.flow_rate.blow_out = 400

4. Accessing Wells and Locations

Well Access Methods:

# By name
well_a1 = plate['A1']

# By index
first_well = plate.wells()[0]

# All wells
all_wells = plate.wells()  # Returns list

# By rows
rows = plate.rows()  # Returns list of lists
row_a = plate.rows()[0]  # All wells in row A

# By columns
columns = plate.columns()  # Returns list of lists
column_1 = plate.columns()[0]  # All wells in column 1

# Wells by name (dictionary)
wells_dict = plate.wells_by_name()  # {'A1': Well, 'A2': Well, ...}

Location Methods:

# Top of well (default: 1mm below top)
pipette.aspirate(100, well.top())
pipette.aspirate(100, well.top(z=5))  # 5mm above top

# Bottom of well (default: 1mm above bottom)
pipette.aspirate(100, well.bottom())
pipette.aspirate(100, well.bottom(z=2))  # 2mm above bottom

# Center of well
pipette.aspirate(100, well.center())

5. Hardware Module Control

Temperature Module:

# Set temperature
temp_module.set_temperature(celsius=4)

# Wait for temperature
temp_module.await_temperature(celsius=4)

# Deactivate
temp_module.deactivate()

# Check status
current_temp = temp_module.temperature  # Current temperature
target_temp = temp_module.target  # Target temperature

Magnetic Module:

# Engage (raise magnets)
mag_module.engage(height_from_base=10)  # mm from labware base

# Disengage (lower magnets)
mag_module.disengage()

# Check status
is_engaged = mag_module.status  # 'engaged' or 'disengaged'

Heater-Shaker Module:

# Set temperature
hs_module.set_target_temperature(celsius=37)

# Wait for temperature
hs_module.wait_for_temperature()

# Set shake speed
hs_module.set_and_wait_for_shake_speed(rpm=500)

# Close labware latch
hs_module.close_labware_latch()

# Open labware latch
hs_module.open_labware_latch()

# Deactivate heater
hs_module.deactivate_heater()

# Deactivate shaker
hs_module.deactivate_shaker()

Thermocycler Module:

# Open lid
tc_module.open_lid()

# Close lid
tc_module.close_lid()

# Set lid temperature
tc_module.set_lid_temperature(celsius=105)

# Set block temperature
tc_module.set_block_temperature(
    temperature=95,
    hold_time_seconds=30,
    hold_time_minutes=0.5,
    block_max_volume=50  # µL per well
)

# Execute profile (PCR cycling)
profile = [
    {'temperature': 95, 'hold_time_seconds': 30},
    {'temperature': 57, 'hold_time_seconds': 30},
    {'temperature': 72, 'hold_time_seconds': 60}
]
tc_module.execute_profile(
    steps=profile,
    repetitions=30,
    block_max_volume=50
)

# Deactivate
tc_module.deactivate_lid()
tc_module.deactivate_block()

Absorbance Plate Reader:

# Initialize and read
result = plate_reader.read(wavelengths=[450, 650])

# Access readings
absorbance_data = result  # Dict with wavelength keys

6. Liquid Tracking and Labeling

Define Liquids:

# Define liquid types
water = protocol.define_liquid(
    name='Water',
    description='Ultrapure water',
    display_color='#0000FF'  # Hex color code
)

sample = protocol.define_liquid(
    name='Sample',
    description='Cell lysate sample',
    display_color='#FF0000'
)

Load Liquids into Wells:

# Load liquid into specific wells
reservoir['A1'].load_liquid(liquid=water, volume=50000)  # µL
plate['A1'].load_liquid(liquid=sample, volume=100)

# Mark wells as empty
plate['B1'].load_empty()

7. Protocol Control and Utilities

Execution Control:

# Pause protocol
protocol.pause(msg='Replace tip box and resume')

# Delay
protocol.delay(seconds=60)
protocol.delay(minutes=5)

# Comment (appears in logs)
protocol.comment('Starting serial dilution')

# Home robot
protocol.home()

Conditional Logic:

# Check if simulating
if protocol.is_simulating():
    protocol.comment('Running in simulation mode')