Hitachi ZA3000 Series, Instruction Manual

Page: 122 / 522

5.1 Various Measurement Methods
5 - 6
This simple standard addition method has two steps. The
standard addition method is conducted with the first samples.
The working curve that was affected by the coexisting substance
obtained by the first step is applied to the second samples
onward (See Fig. 5-5). So, this method is equivalent to the
working curve generation with matrix-matched samples (matrix
matching method).
Fig. 5-5 Working Curve in Simple Standard
Addition Method
This method is effective for measuring a number of samples
similar in matrix composition.
Using the first unknown sample, prepare aliquots by adding a
series of standard solutions as shown in Fig. 5-6. For the
second and subsequent unknown samples, prepare samples
corresponding to only STD1 in Fig. 5-6.
5.1.3 Simple Standard
Addition Method
A
x+2
A
x+1
A
x
-C
x
Concentration
0 C
1
C
2
C1: Standard addition temperature for unknown
sample 1 (1)
C2: Standard addition temperature for unknown
sample 1 (2)
Ax: Absorbance of unknown sample1
Ax+1: Absorbance of unknown C1
Ax+2: Absorbance of unknown C2
x: Reciprocal number of unknown sample1’s
concentration
Absorbance
Working curve for simple
standard addition method
(Unknown sample 1 and
onward)
Working curve for simple
standard addition method
(Unknown sample 2 and
onward)