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3DJH RI
4.8) System suitability:
4.8.1) Definition:
System suitability tests are integral part of chromatographic methods and they
are used to verify the performance of the chromatographic system. The tests are based on
the concept that the equipment, electronics, analytical operations and samples to be
analysed constitute an integral system that can be evaluated as such.
4.8.2) Assessment:
To ascertain the effectiveness of the final operating system, it is subjected to
suitability testing. Replicate injections of the standard preparation are made to demonstrate
adequate system precision. It is performed before the injection of samples.
The resolution is checked to verify the resolution power of the column and to ensure that
closely eluting compounds are resolved from each other. Column efficiency is further
checked based on theoretical plates and asymmetry factor. No sample analysis is
acceptable unless the requirements of system suitability have been met.
4.8.3) Acceptance criteria:
To be determined.
4.8.4) Experiment: Refer 4.1
4.8.5) Observation:
Refer
4.1
4.8.6) Conclusion:
The following system suitability parameters are determined for this method: -
1) Standard solution and reference extract solution to be injected
2) Peaks of all the withanolides are well separated and the resolution is >3 for
Withanoside & Withaferin A in the standard solution.
3) The asymmetric factor (tailing factor) for Withanolides should be < 1.5.
4) The relative retention time of Withanoside IV is about 0.70,
Withanoside V is about 0.89,
Withaferin A is about 0.92, 12-Deoxy withastramonolide is about 0.96 and Withanolide B is
about 1.15.
5) The precision of injection (with minimum of 3 replicates) RSD should be <1.0% for
standard and sample solution.
6) Retention time window
±
3
σ
of mean retention time of the standard or reference extract.
7) Precision in result (The result of QC check sample (reference extract) shall be within
±
10% of the labelled result).