Running Calibration Standards - Agilent Technologies 7500 ICP-MS Operator's Manual

Agilent 7500 ICP-MS ChemStation Operator's Manual
Performing a Quantitative Analysis

Running Calibration Standards

To perform a quantitative analysis you must first prepare and analyze calibration
standards. Usually you will run a blank solution and then a series of standard
solutions containing known concentrations of the analytes. Each calibration
standard contains a different concentration of the analyte, and it is typical to run four
calibration standards, including the blank or 0 standard. Thus the number of points
on a calibration curve corresponds to the number of calibration standards you run.
Although you can run the calibration standards alternately with the unknown
samples, it is advisable to run the calibration standards first. You can then create and
view the calibration curves to determine if the calibration is acceptable. If you need
to re-run the calibration, you can do so before you run the unknown samples.
If you are analyzing samples using a sequence, enter the calibration standards before
the unknown samples in the sample log table. The sequence automatically create the
calibration standards and analyze the unknown samples. You can stop the sequence
after analysis of the calibration standards and check the calibration curve, and then
re-start the sequence to analyze the unknown samples. For information about
running a sequence, see Chapter 8, "Running a Sample Analysis".
Calibration standards need not be comprised of elements all at the same
concentration; they can be made up with elements present at different concentrations
within the same solution. In addition, sets of calibration standards containing
different groups of elements can be run sequentially in the same sequence, and
quantitative analysis performed on the samples for all elements at the same time. For
example, one set of standards containing only transition elements is prepared, along
with a set of standards containing only rare earth elements. The two sets are run
sequentially, followed by the samples, which are quantitated for both sets of
elements at the same time. This is useful when measuring large suites of elements
which may be chemically unstable when combined all together in one set of
solutions.
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