What are research peptides?

Synthetic peptides sold as laboratory reference materials for in-vitro and animal research, labelled research use only. They are not approved medicines.

Are research peptides legal?

They are sold as research chemicals, not as drugs. Several common ones appear on FDA's compounding safety-risk lists and some on WADA's Prohibited List. Each product page states its compound's status.

What does research grade mean?

It means the material is supplied for laboratory research, not for human use. On its own it says nothing about quality; the lot certificate does.

What purity should research peptides have?

Suppliers commonly quote 98-99% or higher by HPLC. A purity figure matters only with the lot, the laboratory and the method attached, plus identity and net content results.

How do I verify a research peptide supplier?

Check for a certificate per lot, a named laboratory you can verify with, identity and net-content results, contaminant screens, and matching names and lots across page, certificate and label.

Are NAD+ and SLU-PP-332 research peptides?

They are sold alongside research peptides but are not peptides: NAD+ is a dinucleotide and SLU-PP-332 a small molecule.

Research Peptides: What They Are and How to Verify Them

Research peptides are synthetic peptides sold as laboratory reference materials for in-vitro and animal research, not as medicines. Most are short chains of amino acids copied from, or modelled on, natural hormones and protein fragments. Because they are not approved drugs, the only assurance of what is in a vial is the supplier’s documentation, which makes testing and traceability the core of buying them.

What counts as a research peptide

A peptide is a chain of amino acids joined by peptide bonds; most research peptides are between 3 and about 40 residues long (see what is a peptide?). “Research peptide” is not a chemical class but a supply category: a peptide sold for laboratory research and labelled “research use only”. Several compounds sold in the same catalogues are not peptides at all, such as NAD+, SLU-PP-332 and 5-amino-1MQ.

Many research peptides are also, or were once, drug candidates. Some are the same molecules as approved medicines, such as tirzepatide; some are investigational, such as retatrutide; and many, like BPC-157 or TB-500, have never been through a full clinical programme. The research-use label means the material is not approved or intended for human or veterinary use, whatever the molecule’s history.

Research peptides by research area

Research area	Examples in our catalogue
Incretin and metabolic receptor agonists	Retatrutide (GLP-3 Reta), tirzepatide (GLP-2 Tirz), survodutide
Tissue-repair models	BPC-157, TB-500, BPC-157 / TB-500 blend
Growth hormone axis	Tesamorelin, CJC-1295, IGF-1 LR3
Mitochondrial and cellular	MOTS-C, SS-31, Epithalon
Neuropeptides	Selank, Semax, DSIP
Copper peptides	GHK-Cu
Melanocortins	Melanotan II, PT-141, KPV
Immune research	Thymosin Alpha-1
Blends	KLOW, BPC-157 / TB-500
Ready-made solutions	Selank, Semax, DSIP, PT-141 and Adamax sprays

What “high purity” should mean

Suppliers of high purity research peptides usually quote an HPLC purity figure, often “99%+”. That number is meaningful only with three things attached: the lot it belongs to, the laboratory that measured it, and the method. Even then, purity is one result of several. A complete certificate also confirms identity, measures how much peptide is in the vial (net peptide content), and screens for contaminants such as endotoxin and heavy metals. Our peptide testing guide explains each of those tests.

How to verify research peptides before you buy

A certificate per lot, not per product. The certificate should name the lot on the vial you are buying, and each size should have its own.
A named laboratory you can check. Look for the lab’s name and a way to confirm the report with the lab itself, such as a verification code.
Identity, not just purity. An identity result (by HPLC retention time against a reference standard, or by mass spectrometry) shows the vial contains the right molecule.
Measured content against the label. Net peptide content shows how many milligrams are really there.
Contaminant screens. Endotoxin, sterility and heavy metals at minimum; some labs add a fentanyl screen.
Consistency. Product name, size and lot should match across the page, the certificate and the label.

Our full checklist is in where to buy research peptides: 10 checks.

How Clean Peptide documents its research peptides

Every size we sell has a certificate on its product page, readable before purchase without an account. Most of our current lots were analysed by ILS Laboratories in San Diego, which states ISO/IEC 17025 accreditation for activities within its published scope and lets anyone check a report on its public portal using the code printed on the certificate. The current position, counted live from the certificates on file:

Laboratory	Sizes on sale	Products	HPLC purity reported	Analysed
ILS Laboratories	20	14	99.26% – 99.90%	3 Sep 2026 – 21 Sep 2026
HYTE Research Division	7	7	99.74% – 99.97%	27 Aug 2026 – 7 Oct 2026
Accurate Test Labs	3	2	99.80%	22 Jul 2026 – 24 Aug 2026
Laboratory not named	1	1	99.62%	1 Jul 2026

31 sizes on sale today carry a certificate. Counted from the certificate data on each product page when this page loads.

The figures in the table come from the certificates themselves. Where a certificate does not report a purity figure, as with the bacteriostatic water’s endotoxin-only report, none is shown.

Regulatory context

Research peptides are not approved medicines, and several common ones are now named in regulatory lists. FDA’s page on bulk substances that may present significant safety risks in compounding lists, among others, BPC-157, TB-500, KPV, AOD-9604, ipamorelin, Melanotan II, DSIP, Selank and Semax, citing limited human safety data. WADA’s 2026 Prohibited List names BPC-157 and TB-500. Each of our product and research pages states the status of its compound. FDA compounding safety-risk list.