A sh-Octapeptide-4 certificate of analysis should answer a specific question: did the supplied batch meet the agreed requirements for the exact commercial grade being purchased? A single “≥99% purity” marketing line cannot answer that question alone.
Quality and procurement teams should review the COA together with the controlled specification, test methods, TDS, SDS, composition statement, and intended application. For the Green Stone Swiss grade, start from the public product-page attributes, then insist that the same identity appear on controlled documents. The page states that full COA, MSDS, and TDS packages are available upon request for verified business inquiries and are not published as open PDF downloads.
First confirm which material the documents describe
CosIng describes SH-OCTAPEPTIDE-4 as a recombinant human peptide produced synthetically to be identical to enkephalin and containing eight amino acids consisting of glycine, histidine, leucine, lysine, phenylalanine, and tyrosine.
The product page currently states:
- INCI Name: sh-Octapeptide-4
- Common Name: MOTS-c, Mitochondrial-derived Peptide
- Appearance: white to off-white powder
- Purity: ≥99%
- Solubility: water soluble
- Origin: China
Check that the quotation, label, specification, COA, TDS, and SDS agree on:
- trade name and grade;
- INCI declaration;
- common name or compositional description used by the supplier;
- physical form (powder versus solution or blend);
- active-content or purity basis;
- manufacturing site and legal supplier;
- batch or lot number;
- document revision and effective date.
If the page common name MOTS-c appears in marketing while the COA uses only the INCI, ask for a written explanation in your document inquiry. If one document refers to neat powder and another refers to a diluted solution, pause approval until the supplier clarifies the difference.
Separate identity, assay, and purity
These terms answer different questions:
- Identity asks whether the material is what the supplier says it is.
- Assay asks how much of a defined component is present, using a stated basis and method.
- Purity asks what else is present, or how much of the material meets an agreed chromatographic or related criterion.
For this powder grade, the page-stated ≥99% purity claim is a useful purchasing expectation, but only if the COA defines:
- the analytical method family;
- the calculation basis;
- related-substance treatment;
- units and whether results are as-is or on another stated basis;
- whether water or residual solvents affect interpretation.
A high purity percentage without method details may be insufficient for incoming inspection or supplier comparison.
Compare every critical result with the agreed specification
A COA is useful only when it is compared with the approved specification for the purchased grade.
For each purchasing-critical attribute, verify:
| Review item | What to check |
|---|---|
| Test item | The attribute appears on both the specification and the COA |
| Acceptance range | The reported result is judged against the same approved limits |
| Method reference | The method identity or code matches the agreed method family |
| Units and basis | Results are expressed in the same units and basis |
| Detection or reporting limit | Limits are stated where “not detected” or “pass” is used |
| Batch identity | Lot number, dates, and sample description match the shipment |
Use the product-page snapshot as a pre-check checklist, not as a substitute for the controlled specification:
| Page-stated attribute | COA / specification question |
|---|---|
| White to off-white powder | Does the batch appearance match the agreed description? |
| Purity ≥99% | Is the numerical result present, in-spec, and method-defined? |
| Water-soluble powder grade | Do identity and form match the neat powder being purchased? |
| Origin China | Is origin or manufacturing site stated where your quality agreement requires it? |
A result marked “pass” may not provide enough information for trend review. Where the attribute is critical, ask whether a numerical result, method reference, detection limit, or supporting chromatogram is available.
Build a risk-based attribute list
Not every possible peptide test belongs on every specification. For this commercial grade, a practical first review often includes:
- appearance;
- identity confirmation appropriate to the peptide;
- purity or assay supporting the ≥99% expectation;
- related-substance or impurity profile where relevant;
- water content or residual solvents where justified;
- microbiological and elemental controls where justified by form and market;
- any additional release tests named on the controlled specification.
Do not copy a pharmaceutical specification onto a cosmetic peptide by default. Equally, do not accept a cosmetic COA that omits the attributes your quality agreement requires.
Review method and change-control readiness
Ask:
- Which attributes are tested on every batch, and which are tested periodically or skip-lot?
- What happens if a result is out of specification, retested, or averaged?
- How are method changes, specification changes, and manufacturing-site changes communicated?
- Can the supplier provide a representative historical COA set for trend review under confidentiality?
- Are document versions controlled, and can superseded specifications be identified?
If the supplier cannot show that the quotation grade, product page, and release methods refer to the same material, the COA is not ready for approval.
Connect documentation review to market and claims review
A conforming COA supports batch release against an agreed specification. It does not by itself prove:
- finished-product safety in every formula;
- claim substantiation for anti-aging or metabolic positioning;
- regulatory acceptability in every sales country;
- interchangeability with another supplier’s sh-Octapeptide-4 grade.
Use the document package as one input to regulatory and claims review. Keep finished-product requirements separate from raw-material release criteria.
Questions to resolve before approval
- Do the quotation, label, specification, COA, TDS, and SDS describe the same powder grade?
- How does the MOTS-c common name map to the INCI and analytical identity?
- Are identity, assay, and purity defined clearly enough for incoming inspection?
- Which attributes are mandatory for every lot?
- Are methods and acceptance criteria controlled and available for review?
- Is a representative sample available under the same grade and document set?
A practical next step
Before sampling at scale or approving a purchase order, inquire for the current controlled specification, SDS, and a representative batch COA for the sh-Octapeptide-4 grade. Compare the reply line by line with your internal quality agreement and intended application.
The product page notes free samples with buyer-paid shipping and MOQ examples of 1 g / 10 g / 1 kg. Ask the sales contact to reconfirm current commercial terms. Use the inquired document package—not the public summary alone—for final approval.
