Horiba Scientific FluoroMax-4 Operation Manual page 92

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FluoroMax -4 & FluoroMax -4P with USB rev. D (30 Jul 2012) Optimizing Data
Using the appropriate wavelength increment
The increment in a wavelength scan is the spacing, in nm, between adjacent data points.
The spacing between the data points affects the resolution of the spectrum, and total
time for acquisition. Consider the required resolution, time needed, and concerns about
sample photobleaching. Most samples under fluorescence analysis display relatively
broad-band emissions with a Lorentzian distribution, so they do not require a tiny in-
crement.
Common increments range from 0.05–10 nm, depending on the sample and slit size. A
first try might be 0.5–1 nm increment. After acquiring the initial spectrum, examine the
results. If two adjacent peaks are not resolved (i.e., separated) satisfactorily, reduce the
increment. If the spectrum is described by an excessive number of data points, increase
the increment, to save time and lamp exposure. A scan taken, using an increment of 0.1
nm, with a peak at full-width at half-maximum (FWHM) of 20 nm, should be charac-
terized with a 1-nm increment instead.
For time-based scans, the increment is the spacing in s or ms between data points. Here,
the consideration is the necessary time-resolution. The time increment dictates the total
time per data point and for the scan in general. Set this value to resolve any changes in
the luminescence of samples as they react or degrade. Time increments often range
from 0.1–20 s.
Set increments in the Inc field, under Monos in the Experiment Setup window.
See the FluorEssence™ on-line help for more information.
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