FDA expects system suitability to be checked using qualified primary or secondary reference standards and any materials necessary to ensure adequate method performance. A new batch of highly pure reference standard material (e.g., a chemical supplier or produced in-house) should be qualified against the primary reference standard. Finished dosage forms or APIs that have not been qualified as reference standards should not be used for system suitability testing. Even when API or a finished dosage form has been properly qualified as a reference standard, it should not be used for system suitability testing if it is the same batch as sample(s) being tested. Written procedures must be established and followed (21 CFR 211.160 and 211.194). All data — including obvious errors and failing, passing, and suspect data — must be in the CGMP records and subject to review and oversight. Records must be complete (e.g., 21 CFR 211.68(b), 211.188, and 211.194) and subjected to adequate review (21 CFR 211.68(b), 211.186(a), 211.192, and 211.194(a)(8)).
