Detector Parameters - Agilent Technologies 7100 User Manual

Using the Agilent 7100 Capillary Electrophoresis System 5
Capillary Electrophoresis, CE

Detector Parameters

The parameters for the detector are set in the DAD tab of the Method Setup
dialog used in the Agilent ChemStation (see Figure 20 on page 93). On the left
hand-side you can define the following settings:
• Used signals, detection and reference wavelengths, bandwidths
• Peak width or detector response time
• Detector stoptime and posttime
Signals, Wavelengths and Bandwidths
Detector parameters allow you to define the detector signals you want to
acquire during the analysis and store in the data file. For each signal the
wavelengths and bandwidths of sample and reference wavelengths are
defined.
It is recommended to do runs without using reference wavelengths to
minimize baseline noise. Reference wavelengths can help to compensate for
signal drifts. As reference wavelengths are usually measured at higher
wavelengths, the baseline noise is increased when using reference
wavelengths. Therefore, it might be appropriate to record the two signals at
the same wavelength; one using the reference wavelength and one without.
The signal you want to store in the data file is displayed below the lamp icon of
the DAD tab of the instrument diagram.
Peak Width
The peak width sets the optimum response time of your detector. If you have
similar peak widths in your electropherogram, set it to the width of one of the
peaks in your electropherogram. If the peak widths are very different you can
use the detector timetable to adjust the peak width setting during the analysis.
If your peak width setting is too narrow, peaks might be not detected
automatically. This will lead to no spectra for the wider peaks being acquired
and in case of peak dependent detection.
Agilent 7100 Capillary Electrophoresis System User Manual 107