Technical data
148 Understanding Your Agilent ChemStation
7 Calibration
Types of Calibration
Figure 35 Two-level calibration curve
For example, if you want to quantify a compound, and the unknown samples
are expected to range from 1 – 10 ng/µl, then a calibration curve should have
at least the two levels as shown in Figure 35 on page 148.
Amount Limits
The ChemStation allows you to define the valid quantification ranges in terms
of absolute amounts for each component.
Multilevel Calibration
Multilevel calibration can be used when it is not sufficiently accurate to
assume that a component shows a linear response or to confirm linearity of
the calibration range. Each calibration level corresponds to a calibration
sample with a particular concentration of components. Calibration samples
should be prepared so that the concentration of each component varies across
the range of concentrations expected in the unknown samples. In this way it is
possible to allow for a change in detector response with concentration and
calculate response factors accordingly.
This multilevel calibration curve has three levels and shows a linear fit
through the origin. This method of linear fit through the origin is similar to the
single-point method calibration. The detector response to concentration is
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