Match the report to the material

Check that the compound name and lot number on the container match the report. Look for the name of the laboratory, the date, and the test methods. For each result, check the units and the range the laboratory used to decide whether the sample passed.

For an example of what belongs on a drug ingredient certificate, see section 11.4 of the FDA’s Q7 guidance.

Identity, purity, and quantity

  • Identity. Does the sample match the expected peptide? Mass spectrometry can compare the measured mass with the expected mass. A test that checks the order of the amino acids can give more detail.
  • Purity. A common method called HPLC separates components of the sample. A peak area percentage describes the share of the detected signal attributed to the peptide under those test conditions.
  • Quantity. How much peptide is present? Look for a separate measurement with units, such as milligrams per vial. A peak area percentage alone cannot tell you that amount.

The results apply to the sample and the tests listed. A purity test alone cannot establish sterility. For examples of how different tests characterize the same peptide sample, see the authors’ comparison of peptide measurements.