Page 24 - Application Handbook - TOC

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.