Molecular Devices SpectraMax

The SpectraMax family of plate readers from Molecular Devices communicate over RS-232 serial. Both models share the same serial protocol (MolecularDevicesPlateReader), but differ in what they can read.

Model	PLR Name	Absorbance	Fluorescence	Luminescence	Temperature Control
SpectraMax M5	SpectraMaxM5	yes	yes	yes	yes
SpectraMax 384 Plus	SpectraMax384Plus	yes	no	no	yes

Connect the reader to your computer via an RS-232 serial cable (or USB-to-serial adapter). Note the serial port name (e.g. COM3 on Windows, /dev/ttyUSB0 on Linux).

Setup

from pylabrobot.molecular_devices.spectramax import SpectraMaxM5

reader = SpectraMaxM5(name="spectramax", port="/dev/ttyUSB0")  # replace with your port
await reader.setup()

For the SpectraMax 384 Plus:

# from pylabrobot.molecular_devices.spectramax import SpectraMax384Plus
#
# reader = SpectraMax384Plus(name="spectramax", port="/dev/ttyUSB0")
# await reader.setup()

Assign a plate to the reader’s loading tray:

from pylabrobot.resources import Cor_96_wellplate_360ul_Fb

plate = Cor_96_wellplate_360ul_Fb(name="plate")
reader.loading_tray.assign_child_resource(plate)

Absorbance

Both the M5 and 384 Plus support absorbance reads. Pass the plate and the wells to read, plus the wavelength in nm.

results = await reader.read_absorbance(plate, plate.get_wells(), wavelength=450)

Reads are configured with keyword arguments, e.g. speed reads and calibration mode:

results = await reader.read_absorbance(
    plate,
    plate.get_wells(),
    wavelength=450,
    speed_read=True,
    calibrate="once",
)

Fluorescence (M5 only)

The SpectraMax M5 supports fluorescence reads.

results = await reader.read_fluorescence(
    plate,
    plate.get_wells(),
    excitation_wavelength=485,
    emission_wavelength=520,
    focal_height=0.0,
)

PMT gain accepts one of "auto", "high", "medium", "low", or a raw integer value:

results = await reader.read_fluorescence(
    plate,
    plate.get_wells(),
    excitation_wavelength=485,
    emission_wavelength=520,
    focal_height=0.0,
    pmt_gain="high",
    read_from_bottom=True,
)

Luminescence (M5 only)

The SpectraMax M5 supports luminescence reads. emission_wavelengths is required.

results = await reader.read_luminescence(
    plate,
    plate.get_wells(),
    focal_height=0.0,
    emission_wavelengths=[460],
)

Temperature control

Both models can hold a temperature between 0 and 45 C.

await reader.set_temperature(37.0)

current = await reader.request_current_temperature()
print(f"{current:.1f} \u00b0C")

await reader.deactivate()

Tray control

Open and close the plate tray:

await reader.open()
# load plate
await reader.close()

Teardown

await reader.stop()