KPV vs GHK-Cu: two tripeptides, one holds copper

KPV and GHK-Cu are both tripeptides, and the copper is what separates them. KPV is three amino acids, lysine, proline and valine, at 353.42 g/mol with nothing attached. GHK-Cu is three different amino acids, glycine, histidine and lysine, holding a copper(II) ion, at 403.91 g/mol. They share no sequence and no parent molecule, and three residues is about all they have in common.

KPV and GHK-Cu side by side

KPV is the last three residues of alpha-melanocyte-stimulating hormone, which places it in the melanocortin family. What is KPV peptide? covers the sequence and where it comes from, and the KPV handling guide puts its concentration table beside the storage rules. GHK-Cu is a different tripeptide, and the copper in the middle of it is what changes how the vial behaves.

What the copper changes

The copper accounts for roughly 63.5 g/mol of GHK-Cu's 403.91, and it drives two handling facts that do not apply to KPV.

• Colour. Copper(II) absorbs red light, so a reconstituted GHK-Cu vial reads blue. KPV holds no metal and goes into solution clear and colourless, so there is no colour check to run on it. Is GLOW peptide supposed to be blue? works through what the blue does and does not tell you.
• Light. A copper complex is light-sensitive, which is one more reason a reconstituted GHK-Cu vial belongs in the fridge and out of direct light. KPV follows the standard rules: water down the inside wall, swirl rather than shake, freezer for the dry powder and fridge once it is mixed.

Take the copper away and you have GHK basic, the same tripeptide with no metal, formula C14H24N6O4 at 340.38 g/mol. It dissolves colourless. GHK-Cu vs GHK basic compares the two forms line by line.

A milligram of either is a similar number of molecules

Both molecules are small, so the per-milligram figures land close together.

One milligram of KPV is about 2.8 micromoles and one milligram of GHK-Cu is about 2.5, which makes GHK-Cu the heavier molecule by about 14% and leaves KPV about 14% ahead per milligram. The gap stays small because both molecules are tripeptides. Compare either against BPC-157 at 1,419.53 g/mol, where a milligram is about 0.70 micromoles, and the same milligram covers roughly a quarter as much material. Size of vial and number of molecules are two different questions.

Where the two meet in one vial

GHK-Cu is sold alone and as a blend component, and KPV is the same. When you want both in a single vial, there are two routes.

A blend label states one combined mass, so the 60 mg on the KPV + GHK-Cu vial counts both peptides together rather than 60 mg of each, and the batch report states how it splits. How much GHK-Cu is in KLOW? works through that arithmetic on the four-peptide version of the same idea. A blend fixes the ratio when the vial is filled, while single vials leave the ratio to you and give each molecule its own report line. Peptide blends vs single vials sets out that trade-off.

Checking a KPV or GHK-Cu vial

The two masses sit about 50 g/mol apart, which is more than enough for a mass spectrometer to separate them, so the identity line is decisive either way. On a single-peptide vial, look for:

• KPV: an observed mass near 353.42 g/mol
• GHK-Cu: an observed mass near 403.91 g/mol
• Either: HPLC purity at 99% or higher, a batch number that matches the vial in your hand, and the name of the independent lab that ran the test

One identity line covers a single-peptide vial. A blend report carries a line per component instead, because each peptide is tested on its own. BPC-157 vs GHK-Cu and KPV sets the three molecules against each other, and how to read a peptide lab report walks through every field.

Both are sold in Canada as research chemicals for laboratory use, not as drugs. Are research peptides legal in Canada? covers how that framing works. This page is general information, not legal advice.

Every KPV and GHK-Cu vial from pepuro ships free, from our Calgary, Toronto and Vancouver distribution centers, the same business day your e-Transfer clears, with a QR code on the vial that opens its independent, third-party lab report.

For research use only. Not for human or animal consumption.