“Purity” is incomplete without an analytical method and an agreed acceptance criterion. A value from a public catalog may refer to a typical result, a historical batch or a particular test method. It should not be treated as a guarantee for a future order.
Clarify the method
Ask which HPLC method is used, what the reported percentage represents and how related substances are handled. For some materials, water content, counter-ion or residual solvent measurements may also affect how the material is interpreted. Identity confirmation is a separate question from purity.
Write the requirement into the quotation
When a project requires a particular threshold, define it in the agreed specification with the method and any additional tests. Compare the batch COA with that document before acceptance. If the material is intended for formulation development, discuss the grade and applicable regulatory review rather than relying on one percentage.
Send the material name, CAS or sequence and your analytical requirements through our quote form.