Case Example: A Comprehensive Quantitative Analysis
As a final example, a quantification of an analyte X with quality assessment by
a surrogate standard is described in the following.
An analysis applied to a 9.5 g soil sample included extraction, drying of the
extract, fractionation, reduction of the fraction volume to 50 μL and
(continued)
sample
matrix
Recovery rate (R)
analytic
procedure
(extraction,
fractionation)
Spiking with
analyte with C 0
measurement
results
measured concentration
of the analyte (C 1 )
R
Blank
no sample
analytic
procedure
(extraction,
fractionation)
measurement
results
only laboratory
contaminations
sample
Surrogate standard method
Analytic
procedure
(extraction,
fractionation)
addition of
surrogate standard with C 0
measurement
results
Measured concentration
of the
surrogate standard (C 1 )
Fig. 6.2 Schemes of blank procedure, recovery rate and surrogate standard approaches
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6 Analytical Quality Control