Page 8 - 2_Pharmaceutical industry
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SCA-130-203



             There, all carbon compounds are oxidized to
            CO 2. To ensure complete oxidation, there is
            an additional catalyst in the combustion tube.
            The resulting CO 2 is then transported to the
            detector in  the main instrument. The NDIR
            detector  of  the  TOC-L  series  contains  a       Depending on the expected concentration or
            tandem cell that consists of a long cell (200       defined  limit  value,  the  system  configuration
            mm) and a short cell (1 mm). By default, the        and  calibration  curve  is  selected.  The
            long cell  is  used for water analysis and the      calculated  amount  of  carbon  is  now
            short cell for solid-sample analysis. To attain     correlates  directly  to  the  area  of  the  wiped
            a higher sensitivity for the analysis of solids,    surface.
            the solid-sample module can also be
            connected  to  the  long,  and  thus  the  more     Practical example:
            sensitive,  measuring cell.  This can be            ■ Instrument/ Measurement parameter
            realized using an upstream switching valve.         Unit:         TOC-LCPH + SSM-5000A
                                                                              (shortcut of IC-flow line)
            This way, the system  can now readily be            Detector cell:  Short Cell
            used for cleaning validation without any loss       Carrier gas:   400 mL/min oxygen (SSM)
            in  flexibility  of  switching  between  water  and   Meas.-typ:    TC
            solid-sample analysis.                              Cal-Curve:    1-Point Calibration curve wiht
                                                                              30μL of 1%C Glucose solution
            ■ Preparation                                       Swab:         Advantec QR-100 quartz glass
            As the TOC analysis involves a sum                                Filter paper (45 mm)
            parameter,  it  is  important  to  ensure  that  the              Prepared at 600°C,15min

            measured carbon really originates  from the         ■ Result
            sampled surface. Some preparation is,
            therefore, important.                                   Compound            TOC-      Recovery
            First, the swabs used  must be carbon-free.                                Result
            This  is  why  fiber  optics  swabs  are  used,     Blank                0,00        101 %
                                                                Tranexamic acid
                                                                                     202 µgC
            which are annealed at 600 °C and are stored
            under dry conditions using an inert gas. The        Anhydrous caffeine   201 µgC     100 %
            same pretreatment is required for the ceramic       Isopropylantipyrine   210 µgC    105 %
            boat.  All  tools  used,  such  as  tweezers  and   Nifedipine           212 µgC     106 %
            glass containers must be free from carbon.          Gentashin ointment   200 µgC     100 %
                                                                                     209 µgC
                                                                                                 104 %
                                                                Rinderon ointment

            ■ Swab test                                         (Further information is available in the
            For the wiping test, two pretreated swabs are       application note Japan TOC O41)
            sampled, the lower swab is moistened with
            water and the defined surface is wiped
            according to the prescribed procedure. The
            used swab is now folded, placed in the clean
            ceramic  boat  and  transferred  to  the  TOC
            measuring system.
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