AHK-Cu Testing | Identity & Purity Check

What AHK-Cu is

AHK-Cu is a tripeptide — alanine, histidine, lysine — complexed with a copper(II) ion, and it is the near-twin of the far more common GHK-Cu (which swaps the alanine for glycine). Both are small, very polar molecules whose copper complex is the whole point of the product and also its analytical weak spot: the complex is fragile, an acidic diluent strips the copper, and on a reversed-phase column the peptide runs early and close to the solvent front. AHK-Cu is sold almost exclusively on the research-chemical market with no regulated manufacturing behind it, and because the two copper tripeptides look alike on a label and price very differently, an independent identity check is worth more here than for most compounds.

Why get your AHK-Cu independently tested

GHK-Cu substitution: AHK-Cu and GHK-Cu differ by a single residue and are easy to mislabel — deliberately or otherwise. Retention-time and UV-spectral matching against an AHK reference standard, run alongside the GHK-Cu standard we keep on hand, tells the two apart.
Copper-complex integrity: a colourless reconstituted solution or a peptide peak with no copper signature suggests the complex did not survive manufacture or storage. Our prep for copper peptides is deliberately acid-free so we measure what arrived, not what our diluent did to it.
Content on a very small molecule: at ~400 Da before copper, a small error in fill mass is a large fraction of the label claim. The net-peptide assay reports measured milligrams of AHK peptide per vial against the declared amount.
Salt and hydration weight: copper peptides are typically supplied as salts and carry water. Gravimetric fill can look right while the actual peptide mass is short — only a content assay against a reference standard separates the two.

What we measure on AHK-Cu

Every AHK-Cu certificate reports identity (retention-time and UV-spectral match against a certified AHK reference standard), chromatographic purity as area percent, and net-peptide content in milligrams per vial, by reversed-phase HPLC with diode-array detection. Appearance is reported at the vial level — an intact copper complex reconstitutes with a characteristic blue tint — and solution pH is available as an add-on. The copper ion dissociates on the column, so the certificate states the result for the AHK peptide; that is the honest way to report a copper peptide by HPLC.

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; because AHK-Cu is far less common than GHK-Cu, a reference standard may need to be sourced before analysis, which can affect turnaround. KMD Analytical is an independent laboratory. We do not perform mass spectrometry, sterility, endotoxin, heavy-metal, or residual-solvent testing, and we do not quantify free copper.

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.

AHK-Cu testing — FAQ

Can you tell AHK-Cu from GHK-Cu?

Yes. They differ by one residue and separate under our RP-HPLC-UV method, and we keep a GHK-Cu reference standard on hand to run beside the AHK standard. Identity is a retention-time and UV-spectral match against the compound named on your label, so a vial sold as AHK-Cu that actually holds GHK-Cu will not conform.

Do you measure the copper?

Not directly. The copper ion dissociates from the peptide on the column, so what the chromatography quantifies is the AHK peptide, and the certificate says so. The intact complex shows itself in appearance — a blue tint on reconstitution — which is reported on every certificate. Quantifying copper itself would need ICP-MS, which is outside our scope.

Why does the prep matter for copper peptides?

Acid strips the copper from the peptide. We reconstitute and dilute copper peptides without acid so the vial is measured as it was made, not as our diluent changed it. That is a deliberate method choice for this compound class.

Test your AHK-Cu →Verify a certificate Pricing & turnaround

AHK-Cu (Copper Tripeptide) Testing & Verification