Page 19 - Application Handbook - TOC
P. 19
Sum parameter – Total Organic Carbon
TOC determination in ultrapure water –
Comparison of the various oxidation
SCA-130-201 techniques
Ultrapure water is one of the most widely Water Purified is used in the manufacture of
used excipients in the production of pharmaceuticals that do not require any other
pharmaceuticals. It is also used for cleaning standard. The organic content is determined
purposes. Different application areas require either via the TOC value (0.5 mg/L) or via the
different grades of ultrapure water quality. permanganate test (purified water in bulk).
These grades are defined in the European
Pharmacopoeia, which distinguishes between ■ TOC determination in ultrapure water
‘Purified Water’, ‘Highly Purified Water’ and Two oxidation techniques are now commonly
‘Water for Injection’ (‘The United States used in TOC analysis:
Pharmacopoeia, however, does not use the 1. Catalytic combustion, where carbon
same classification as the European compounds are converted into CO 2 using a
Pharmacopoeia’). catalyst under high temperatures with
subsequent detection of the resulting CO 2
using an NDIR detector.
2. Wet chemical oxidation, which uses a
combination of UV irradiation and persulfate
for oxidation. Both methods can be applied
for the determination of ultrapure water.
Water for injection is used for the
preparation of injection solutions and is
produced by distillation. The TOC content
may not exceed 0.5 mg/L (water for injection
in bulk).
Water Highly Purified is a sterile ultrapure
water for the manufacture of pharmaceuticals ■ TOC-L CPH: Oxidation via catalytic
that do not require a ‘Water for Injection' combustion
standard. It is also often used for the final The TOC-L CPH uses the proven catalytic
rinse during cleaning and is usually produced oxidation at 680 °C.
by reversed osmosis. The TOC content may
not exceed 0.5 mg/L.
.
