Ratio Qualifiers For Selective Detection Of Compound Classes - Agilent Technologies 1200 Infinity Series User Manual

5
Optimizing the Detector
Optimizing Selectivity

Ratio Qualifiers for Selective Detection of Compound Classes

Ratio qualifiers can be used where, in a complex sample, only one particular
class needs to be analyzed — a parent drug and its metabolites in a biological
sample, for example. Another example is the selective analysis of derivatives
after pre- or post-column derivatization. Specifying a signal ratio that is
typical for the sample class is one way of selectively plotting only those peaks
that are of interest. The signal output remains at zero so long as the ratio is out
of the user-specified ratio range. When the ratio falls within the range, the
signal output corresponds to the normal absorbance, giving single, clear peaks
on a flat baseline. An example is shown in
on page 99.
Figure 27
98
Wavelength Selection for Ratio Qualifiers
Figure 27 on page 98 and
Agilent 1200 Infinity Series DAD User Manual
Figure 28