Page 16 - 2_Pharmaceutical industry
P. 16
SCA-130-207
■ Shimadzu TOC-System The injection volume is determined, based on
Shimadzu offers two systems that are ideally the highest calibration standard. For 20mg/L
suitable for TOC determination in ultrapure the default injection volume is 50µl.
water. The TOC-VWP/WS uses wet-chemical
oxidation, whereas the TOC-LCPH uses
catalytic combustion at 680 °C.
Both types of instrument with their different
oxidation methods can be used for TOC
determination in accordance with the United
States Pharmacopeia (USP <643>) and the
European Pharmacopeia (EP 2.2.44).
Figure.2 : Calibration Curve 20mg/L, graphic
The calculation of the limit of detection limit
according to DIN 32645:
■ Linear dynamic range from 0,2 – 20mg/L Characteristics
To prove the required dynamic range, a Slope a: 5,503
calibration with TOC-L CPH (with high Intercept b: 0,091
sensitivity catalyst) was carried out in a range Correlation coefficient r: 0,9999
Result uncertainty:
33,3%
of 1,0 mg/L – 20mg/L. Probability of error (a): 5,00%
Number of injections: 2
© DINTEST
Limit of detection: 0,2mg/L
These results show that the TOC-CPH with
high sensitivity catalyst covers the required
linear dynamic range from 0,2 – 20mg/L. This
means both applications, purified water and
this extraction solution can be measured with
a single TOC-L CPH instrument.
■ Recommended Analyzer / Configuration
TOC-L CPH with high sensitive catalyst
ASI-L (40ml), external sparge kit
Figure.1 : Calibration Curve 20mg/L, results
■ Source: www.usp.org
For the dilutions, the automatic dilution
function of the TOC-L system was applied.