Match the lab results to the product.
A useful Certificate of Analysis identifies the relevant product and the corresponding batch number. Match both to the product you are reviewing, and check the laboratory name and testing date.
Look closely at purity and identity.
Look for the measured purity percentage and the method used to determine it. Review identity testing alongside purity to understand how the laboratory identified the material. Purity and the amount of peptide in a vial are different measurements; one does not establish the other.
Check what else was tested.
Review any results for impurities or potential contaminants, such as residual solvents, heavy metals or microbial contamination. Look for the test method, reported result and any stated limits. A purity percentage alone does not show that these additional tests were performed. If a result is missing or unclear, ask for clarification before drawing conclusions about quality.
General research education. Review product-specific documentation and the stated intended use alongside this guide.