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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.
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