Reagent Blank Value; Eluate Blank Value - Endress+Hauser analytikjena multi N/C UVHS Operating Manual

multi N/C UVHS, multi N/C pharma UV
Diluent indication
Calculation of the sample con-
centration
3.6.2

Reagent blank value

3.6.3

Eluate blank value

I = V x (V – N /N
DiBV DiBV Sample P
I = I – I
eff Raw DiBV
V : Diluent blank value
DiBV
V Sample volume
Sample
I : Effective integral
eff
N : Number of units of the primary sample
P
N : Number of units of the diluent
D
I : Raw integral
Raw
I : Diluent integral
DiBV
Proportions of the primary probe: in total proportions (e.g., 10 parts in 100 parts)
This means that 10 ml of the primary sample is filled to a total volume of 100 ml with
dilution water.
A 1:1 dilution ratio equals I
To calculate the sample concentration c, the sample volume and the dilution ratio are
used:
c = m/V x N /N
Sample D P
The following equation applies for the linear calibration function:
c = (k x I + k )/V x N
1 eff 0 Sample
If the user dilutes a sample and enters the dilution ratio in the software, the software
automatically calculates the concentration of the undiluted primary sample and outputs
it to the analysis report.
Especially for the measurement of low TOC concentrations, the blank value (TIC/TC con-
tent) of the reagents used must be taken into account.
The following reagent blank values can be taken into account for all measurements:
H PO (TIC branch reagent): IC blank value
¡
3 4
¡ Na S O (TC branch reagent, i.e. for the UV reactor): TC blank value
2 2 8
The reagent blank value can be determined separately and entered manually in the soft-
ware. Measuring the reagent blank value before a series of analyses and letting the soft-
ware determine the blank value is recommended, however. The determined blank val-
ues (in area unit = FE) refer to the amount of reagent dosed.
It is good practice to always determine the reagent blank value again when the reagent
is created. Otherwise, the software will use the last value.
The reagent blank values for the reagents used can be determined individually or as a
group. For multiple determinations, separate determination provides the best results.
The eluate blank value is a special blank value for samples from cleaning validation or
eluate preparation. It corresponds to the TOC content of the ultrapure water used which
has been used, e.g., to extract/eluate swabs.
The eluate blank value is a fixed method parameter. The user can activate or deactivate
the eluate blank value in the method. The user can optionally determine the eluate
blank value separately and enter it in the software manually.
x V )
D Sample
= 0.
DiBV
/N
D P
Function and design
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