What to require on a retatrutide research COA
This is a specification-literacy page for laboratory purchasers comparing retatrutide certificates of analysis. It is not a consumer buying guide, not a catalog of other vendors, and not a use protocol. Not for human consumption. PureLab Performance, Morgan Hill, California.
The product listing is Retatrutide — Research Peptide. Posted lots live on the lot library. How to read the fields: How to read a GLP-1 peptide COA.
A certificate is useful only if it answers four questions about the vial in front of you: which lot, which laboratory, what the chromatogram actually measured, and whether the fill matches the label. A purity percentage with no lot, no named lab, and no content-versus-label line is a claim, not a specification.
1. Require a lot match
Three strings have to be identical: the lot on the vial, the lot on the PDF, and the lot on the product page. A certificate for the right peptide and the wrong lot is evidence about a different batch.
On this catalog the published retatrutide lot is fghe8m6 (reference PLP-RTT-010), a 30 mg label claim. A 5 mg, 15 mg, or 20 mg vial is not this lot. If a vendor will not print the lot on the listing, stop there. Procurement note: where to buy retatrutide for laboratory research.
2. Require a named laboratory
The report should name a laboratory that can be found without the vendor: legal name, city, method, and a date. Lot fghe8m6 was assayed by Krause Analytical, Austin, Texas, HPLC-UV-MS, USP/NF 621, report issued 5 August 2026.
A logo in a header is not a laboratory. A PDF that cites “independent testing” without a lab you can look up is marketing. If the same file appears under three lab names, treat it as decoration.
3. Separate HPLC purity from fill and from label
Chromatographic purity is a peak-area ratio. HPLC separates the sample; a UV detector records a chromatogram; the main-peak area is reported as a fraction of total integrated peak area. For lot fghe8m6 that number is >99.9%.
That figure is not the milligrams in the vial. It is not the label claim. Salts, residual water, residual solvent, and fill variation sit in the gap. Vendors print the peak-area ratio largest because it is the flattering number. Require both lines, or you are reading half a result. Background: peptide purity and HPLC.
4. Require mass-spectrometry identity
Purity asks how much of the chromatogram is the main peak. Identity asks whether that peak is the named peptide. On lot fghe8m6, identity is confirmed — mass spectrometry versus an authentic standard.
Confirmed identity plus high chromatographic purity is a strong pair. Confirmed identity of a light fill is still a light fill. Retatrutide still has no PubChem compound record; CAS, formula, and molecular weight on the specification block are supplier-supplied. MS-versus-standard is the identity check that is actually lot-level.
Worked example: lot fghe8m6, 87.6% of label
| Field | Lot fghe8m6 |
|---|---|
| Compound | Retatrutide (research peptide) |
| Lot | fghe8m6 |
| Label claim | 30 mg |
| Chromatographic purity | >99.9% |
| Content versus label | 87.6% (26.3 mg of 30 mg stated) |
| Identity | Confirmed — MS vs authentic standard |
| Method | HPLC-UV-MS |
| Standard | USP/NF 621 |
| Laboratory | Krause Analytical, Austin, Texas |
| Report issued | 5 August 2026 |
Excellent chromatography. Light of the 30 mg claim. We published 87.6% because that is what the laboratory returned. Lot page and PDF: /coa/retatrutide-fghe8m6/.
What a generic purity claim does not tell you
A vendor page that says “third-party tested, HPLC 98%+” without a lot string, without the laboratory’s name, and without content versus label has not given you a specification. Those three omissions are the usual ones. They are also the ones that make two certificates look interchangeable when they are not.
Require the public lot page, not a badge. If the certificate is not on the open web, you cannot check whether the lot on the vial is the lot on the PDF. Our public records: /coa/.
What to open before you order
- The retatrutide product page — lot on the listing.
- The matching lot record — currently fghe8m6 — named lab, method, date, purity, content versus label, identity.
- The reading guide: How to read a GLP-1 peptide COA.
- If the intended use is anything other than in vitro laboratory research, do not order it here.
Related laboratory pages
- Lot certificates of analysis
- Retatrutide product page
- How to read a GLP-1 peptide COA
- Where to buy retatrutide for laboratory research
- What Research Use Only means
- GLP-1 research peptides hub
Questions: info@purelabperformance.com or (408) 208-2430. PureLab Performance, Morgan Hill, California.
Research Use Only (RUO). Retatrutide supplied by PureLab Performance is for in vitro laboratory research only. It is not a drug, not a dietary supplement, not food, and not for human or veterinary use. It is not intended to diagnose, treat, cure, or prevent any disease. No statements on this page have been evaluated by the FDA. Not for human consumption.