Agilent Technologies 1260 - Page 125

Agilent 1260 Infinity DAD and MWD User Manual 125
How to optimize the Detector
6
Optimizing for Sensitivity, Selectivity, Linearity and Dispersion
Because the detector averages absorbance values that are calculated for each
wavelength, using a wide bandwidth does not negatively impact linearity.
The use of a reference wavelength is highly recommended to further reduce
baseline drift and wander induced by room temperature fluctuations or
refractive index changes during a gradient.
An example of the reduction of baseline drifts is shown in Figure 55 on
page 125 for PTH-amino acids. Without a reference wavelength, the
chromatogram drifts downwards due to refractive index changes induced by
the gradient. This is almost completely eliminated by using a reference
wavelength. With this technique, PTH-amino acids can be quantified in the low
picomole range even in a gradient analysis.
Figure 55 Gradient Analysis of PTH-Amino Acids (1 pmol each), with and without
Reference
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