ARA-290 Testing & Verification
Independent, third-party analysis of your ARA-290 (cibinetide) sample by RP-HPLC-UV. This is an uncommon compound with an uncommonly thin verification record, which is precisely the case where measuring the specific vial matters.
What ARA-290 is
ARA-290, also known as cibinetide, is a short synthetic peptide of eleven residues whose sequence corresponds to a solvent-exposed face of helix B of erythropoietin — hence its other names, helix B surface peptide (HBSP) and pHBSP. It is a linear peptide with no disulfide bond and no lipid modification, but it does carry one structurally distinctive feature: a pyroglutamate residue at the N-terminus, formed by cyclization of the N-terminal glutamine or glutamate. It contains no tryptophan or tyrosine, so it has no strong ultraviolet chromophore and is detected at 214 nm on the peptide bond. ARA-290 is an investigational compound rather than an approved drug, it is expensive per milligram relative to common research peptides, and it is uncommon enough that few sellers or buyers have ever seen a chromatogram of it — all of which is context for why an independent measurement is worth having.
Why get your ARA-290 independently tested
- The pyroglutamate N-terminus is a manufacturing variable: ARA-290's N-terminal residue is a cyclized pyroglutamate, and cyclization is a step that can be incomplete. Material carrying the open-chain glutamine or glutamate form instead is a different molecule with different polarity and different reversed-phase retention. Identity by co-elution with a certified reference standard, plus area-percent purity, is how a batch with partial or absent pyroglutamate formation shows up as a non-matching or extra peak.
- High cost per milligram creates underfill incentive: ARA-290 costs materially more per milligram than the common research peptides it is stocked alongside, and it is shipped in small vials where a short fill is hard to notice. The net-peptide assay reports the milligrams of peptide actually present, separated from counterion salt, residual moisture, and any bulking agent, so the labeled figure can be checked rather than assumed.
- Deamidation-prone residues in the C-terminal half: the sequence includes asparagine adjacent to serine, one of the fastest-deamidating motifs in peptide chemistry, along with glutamine residues that deamidate more slowly. Deamidation proceeds through a succinimide intermediate and yields aspartate and isoaspartate products — closely related substances that elute near the parent peak. Chromatographic purity as area percent quantifies how much of the UV-absorbing material is the main peak versus these related forms, on the specific vial you received rather than on the batch a supplier tested months earlier.
- A thin verification record and no aromatic chromophore: because ARA-290 is rarely tested, supplier certificates for it are frequently generic, recycled between batches, or simply absent, and there is no widely circulated reference chromatogram for buyers to compare against. The compound also lacks tryptophan and tyrosine, so the UV spectrum adds little discriminating power and identity rests primarily on retention-time match to a certified standard. Both facts point the same direction: the only reliable statement about a given vial is one produced by running it against a real standard.
What we measure on ARA-290
Each ARA-290 sample is analyzed by reversed-phase HPLC with UV/diode-array detection at 214 nm and compared against a certified ARA-290 (cibinetide) reference standard. The certificate reports exactly three results: identity, by retention-time match to the reference standard run under identical conditions, with UV-spectral comparison as supporting evidence (the sequence carries no tryptophan or tyrosine, so the spectral contribution is limited and retention time is the primary evidence); chromatographic purity, as area percent of the main peak against total integrated peak area; and net-peptide assay, as milligrams of peptide per vial.
Every result is issued as a certificate of analysis you — or anyone you forward it to — can verify cryptographically. Reporting identity, purity, and milligram content is the point: a vial can be pure and still underfilled, so we report all three. More on purity vs. net-peptide content and how to read a peptide COA.
Our scope — stated plainly
Testing is RP-HPLC-UV against a certified reference standard. ARA-290 is a genuinely uncommon compound, so a certified reference standard will often need to be sourced before analysis — that lead time is confirmed with you before we proceed. We do not perform mass spectrometry, sterility, endotoxin, heavy-metal, or residual-solvent testing. KMD Analytical is an independent laboratory and does not sell peptides.
KMD is an independent RP-HPLC-UV lab. We do not run LC-MS / mass-spec, sterility, endotoxin, or heavy-metal testing. If your job needs a capability we don't have, we'll say so.
ARA-290 testing — FAQ
Is cibinetide the same thing as ARA-290?
Yes. Cibinetide is the assigned nonproprietary name for the compound developed as ARA-290, and the same material also appears in the literature as helix B surface peptide, HBSP, or pHBSP. All of these refer to the same eleven-residue erythropoietin-derived peptide, and we test it under whichever name is on your vial.
Can you confirm the pyroglutamate N-terminus is intact?
Not directly, and we will not claim otherwise. What RP-HPLC-UV can do is compare your sample's retention against a certified ARA-290 standard: the open-chain form is more polar than the cyclized pyroglutamate form and elutes differently, so material that is largely uncyclized typically fails to co-elute with the standard, or shows an additional resolved peak that is captured in the area-percent purity figure. Confirming the chemical structure of that peak — proving it is the open-chain form specifically — requires mass spectrometry, which is outside our scope.
Why does ARA-290 take longer to turn around than a common peptide?
Every result we issue is referenced to a certified standard, and standards for uncommon compounds are not something we keep on the shelf. For ARA-290 we usually have to source one before your sample can be run, and that sourcing step sets the timeline more than the analysis itself does. We tell you the expected lead time before you commit, rather than accepting the sample and letting it sit.
What does net-peptide content mean on a small, expensive vial?
It is the measured milligrams of peptide in the vial, as distinct from the total weight of the lyophilized powder. That powder also contains counterion salt, residual moisture, and any bulking agent. On a high-cost compound sold in small vials, the gap between labeled mass and actual peptide mass is where the money is, so this is the number most worth checking against the label.
Other peptides we test
Retatrutide · Cagrilintide · Tesamorelin · BPC-157 · see the full panel.