How to Read a Oxytocin Certificate of Analysis (COA)
A Certificate of Analysis is only useful if you know which number on it matters for the compound in front of you. For Oxytocin, the informative checks are not the same as for a generic short peptide.
Overview
Confirm the weight near 1007.2 for the intact loop. The critical extra check is whether any material appears at roughly double that weight — that means two molecules have joined together through swapped sulfur bonds. Purity percentage alone can look fine while that is happening.
What Oxytocin actually is
Oxytocin is a natural hormone made in the brain, familiar from research on social bonding and childbirth. It also holds a place in chemistry history: it was the first hormone of its kind ever built synthetically, in 1953, and that work won a Nobel Prize two years later.
Supplied for laboratory research use only — not for human or animal use.
Third-party tested by HPLC and LC-MS, ≥99% purity, with a Certificate of Analysis on every order. Ships across Canada.
Technical detail below
Assays that are informative for Oxytocin
What to check on the COA
Confirm the molecular ion at 1007.2 Da for the intact cyclic monomer. The critical additional check is dimer content: a species at roughly twice the monomer mass indicates intermolecular disulfide exchange. Purity by HPLC alone can look acceptable while dimer accumulates, so the mass spectrum matters here more than for linear peptides.
Disulfide-linked dimers, deamidated species (+1 Da), and reduced open-chain forms.
Verify a Popular Peptides batch
Every batch is third-party tested by HPLC and LC-MS with a published Certificate of Analysis (≥99% purity). Enter a lot number to pull the COA for the exact vial in front of you.
What Oxytocin is studied for
The largest behavioural-neuroscience literature of any peptide in this catalogue.
Studied for interactions with cortisol and stress-response signalling.
Its originally characterised role, and the basis of its clinical history.
Oxytocin and vasopressin differ by two residues, and receptor cross-reactivity is a persistent methodological theme.
Summarizes published preclinical literature — see the selected references below. Provided for research reference only; not a claim of efficacy or a description of human use.
- Gimpl G, Fahrenholz F The Oxytocin Receptor System: Structure, Function, and Regulation. Physiol Rev. 2001.
- Browse current Oxytocin literature on PubMed
References describe in-vitro and preclinical research and are listed for reference only — not evidence of efficacy and not a description of human use.
More Oxytocin reference
Lyophilized and reconstituted storage conditions, plus the practical working window.
Diluent selection, dissolution behaviour, and the calculator preset for this compound.
Which solvents work, why, and what abnormal dissolution behaviour indicates.
The specific chemical routes by which this molecule breaks down, and how to limit each.
Compound-specific bench practices, and the errors most often made with this molecule.
What to inspect on arrival, and which conditions actually warrant rejecting a vial.
Questions specific to this compound — structure, chemistry, and common misconceptions.
Purity & COA reference for other compounds
Reviewed for research-use compliance by Kobi Williams, Founder — Popular Peptides Canada. Last reviewed 22 July 2026.
Oxytocin is supplied strictly as a research chemical for in-vitro laboratory and research use only. It is not intended for human or animal consumption, diagnostic, or therapeutic use. This page is educational laboratory-handling reference information — not medical advice, not usage guidance, and not a protocol.