Keep the measurements distinct
Chromatographic purity describes the relative detected components under the stated method. Identity assessment addresses whether the material is consistent with the intended product. Net peptide content concerns peptide material relative to non-peptidic components such as counterions and moisture. These are related but not interchangeable questions.
For background, see Bachem’s quality-control guide. Its examples and product grades belong to that source and are not specifications for Celtre products.
Questions to put to a supplier
- What property does each reported percentage describe?
- Which method and sample or batch does the result refer to?
- Is identity assessed separately, and what record is available?
- What quantity basis is used in the quotation and label?
- Which required assessments are not included?
Avoid a common procurement shortcut
Do not treat a catalog purity claim as a measurement of every vial’s contents. Likewise, do not use one result to infer unreported properties. Ask for the records needed by your responsible technical team and document any limitation that affects acceptance.
Keep this separate from use instructions
This guide explains document-review questions for research procurement. It does not provide preparation, dosing or human-use instructions. Product-specific specifications and relevant analytical requirements should be reviewed by the responsible qualified personnel.