Time-Resolved Fluorescence; Luminescence; Functional Description - Molecular Devices SpectraMax M2 User Manual

2. Principles of Operation
2.6.
2.7.
2.8.
SpectraMax M2 & SpectraMax M2e Multi-mode Plate Readers User Guide — 0112-0102 Rev. D
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TIME-RESOLVED FLUORESCENCE

Time-resolved fluorescence is a secondary mode for the SpectraMax M2 and
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SpectraMax M2 , so performance is not comparable to instruments that specialize in
time-resolved fluorescence, such as the SpectraMax M5, Analyst HT and Analyst GT.
In normal fluorescence mode, readings are taken while the lamp is on. The most common
limitation to sensitivity in normal fluorescence is excitation energy or background
fluorescence that cannot be eliminated from the emission signal. Since the lamp is the
source of excitation energy, turning it off provides the best means of eliminating
background excitation.
Time-resolved fluorescence is performed by flashing the excitation lamp and, after it is off,
collecting the delayed emission for a period of time before the lamp is flashed again.
Lanthanide dyes are frequently used to delay the fluorescence long enough to measure it
after the lamp is turned off.
To assist with proper collection of data, you can also select when to start and end data
collection (within the limits of the system-the minimum is 50 µs and the maximum is
1450 µs in 200-µs steps).

LUMINESCENCE

The SpectraMax M2 and SpectraMax M2
photomultiplier tube detection. Some luminescence applications, such as gene reporter
assays, may require a luminometer with photon counting detection for greater sensitivity,
such as the SpectraMax M5, Analyst GT or Analyst HT, or LMax II.
In luminescence mode, no excitation is necessary as the species being measured emit light
naturally. For this reason, the lamp does not flash, so no background interference occurs.
A dark estimate is done over a dark reference, and multiple readings are averaged together
into one reading per well.
You can choose the wavelength where peak emission is expected to occur. In addition,
multiple wavelength choices allow species with multiple components to be differentiated
and measured easily. In luminescence read mode, no emission cutoff filter is used. The
default setting for luminescence is the "zero order" position where the grating
monochromator acts as a mirror that reflects all light to the PMT detector.

FUNCTIONAL DESCRIPTION

The full power of a SpectraMax M2 and SpectraMax M2
instrument is controlled using SoftMax Pro software running on a computer connected to
the instrument. For a complete description of the modes of operation, how to choose
instrument settings, etc. refer to the SoftMax Pro User Guide.
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are microplate spectrofluorometers with
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can only be harnessed when the