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3. Is there information
demonstrating that the
method system suitability
tests and controls as
specified in the SMPR worked
appropriately and as
expected? If no, please
specify.
blank injection is missing, check Standards at different concentrations are described.
4. Based on the supporting
information, is the method
written clearly and concisely?
If no, please specify the
needed revisions.
yes
5. Based on the supporting
information, what are the
pros/strengths of the
method?
definitely separation power and Speed.
6. Based on the supporting
information, what are the
cons/weaknesses of the
method?
Methyl xanthenes (besides caffein) are missing. Gallic acid is missing though it maybe
important. The method has been applied only for green tea and not for fermented black
tea.
7. Any general comments
about the method?
Excellent Method for green tea (and products). The method should also be tested for
black tea. Usually a stabilizing solution (like in the ISO-method) should be used, to the
instability of some catechins in solution.
Some of the Validation Parameters doesn't fulfill the requirements of the SMPR's, e.h.
recovery rate for caffeine only 78.7% for a dietary Supplement.
Do you recommend this
method be adopted as a First
Action and published in the
Official Methods of Analysis
of AOAC INTERNATIONAL?
Please specify rationale.
The method could be recommended (because of speed and resolution) after having
tested for black tea as well and including theobromine and theaphyllin like it is required
by the SMPR. Some of the Validation data should be repeated or verified by the
applicants.