horiba FluoroMax-3, Руководство по эксплуатации

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FluoroMax-3 v. 3.1 (3 Mar 2006) Optimizing Data
5-11
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
photobleaching of the sample. Most samples under fluorescence analysis display rela-
tively broad-band emissions with a Lorentzian distribution, so they do not require a tiny
increment.
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 the react or degrade. Time increments often range from
0.1–20 s.
Set increments under the
Monos icon in the Experiment Setup window.
See the FluorEssence™ on-line help for more information.