The COA Guide · By Synthesis Peptides
How to read a Certificate of Analysis
A practical reference for checking lot numbers, purity, measured peptide content and testing scope. Read the complete guide below; no email required.
- Match the certificate to the lot
- Read each result alongside its method
- Record the scope and limits of testing
1. Match the lot before reading the results
A certificate documents a particular batch. Compare the product name, variant and lot number on the vial with the report. A certificate from another lot is not a substitute for the report that belongs to yours.
- Product name and variant match the label
- Lot number matches exactly
- Report identifies the laboratory and testing date
2. Keep purity and peptide content separate
Purity and measured peptide content are separate results. Find both entries on the certificate. Do not infer the amount in the vial from a purity percentage.
Read each value alongside its method and units. If a result, unit or method is missing or unclear, ask for clarification before recording it.
3. Check which tests the report actually includes
Identity, purity, peptide content, heavy metals, sterility, endotoxin and closure integrity are separate checks. Review the tests listed on this specific report; do not assume an unlisted test was performed.
A pass/fail badge alone does not show the same detail as a lot-specific report with methods and results.
- List the tests reported for this lot
- Note the method, result and any stated acceptance limit
- Flag missing information and unresolved questions
4. Keep the report with your batch record
Save the original certificate, its source and the date you accessed it. Keep the lot number, variant and any clarification from the supplier together so the record can be checked later.
5. Read the certificate within its scope
A Certificate of Analysis reports only the tests and results shown on that document. It is not a substitute for assessing whether a batch meets the requirements of a particular laboratory project.
Synthesis Peptides products are for laboratory research only. Use the published COA library to locate the report for the lot you are reviewing.
Questions
Frequently asked questions
Are these products for human use?
No. Products are for laboratory research only. They are not for human consumption, diagnostic or therapeutic use.
Are your peptides third-party tested?
Yes. Every batch is independently tested, with a Certificate of Analysis reporting exact peptide content per vial.
How do I verify a batch?
Match the lot number on your vial to the published Certificate of Analysis. Review that lot's results and testing methods.