GHK-Cu 50mg vs 100mg: Cost per mg, Vial Fill & Storage

Research use only. Not for human consumption. Not evaluated by Health Canada. This guide covers specifications, storage and documentation. It gives no dosing or usage guidance.

In short.

• Same compound (the GHK tripeptide bound to copper), same independent lab testing, a COA for each lot.
• The 100mg vial costs about 23% less per mg: $0.85 against $1.10 at one-time prices.
• Once reconstituted, the full vial is on one 30-day clock. Choose by how much material your work needs within one window.

Side by side.

Prices in CAD as listed on 26 Sept 2026. Subscription pricing is 15% lower on both sizes, so the per-mg gap holds.

What's the same.

GHK is a three-amino-acid peptide: glycine, histidine and lysine. It occurs naturally in human plasma, saliva and urine, and the research literature describes it working as a complex with copper(II). The free peptide (glycyl-L-histidyl-L-lysine) has a molecular weight of 340.38 g/mol and the copper complex, also called prezatide copper or copper tripeptide-1, 402.92 g/mol.

Vial size does not change the compound or how it is checked. Every Vitaliti batch comes from solid-phase synthesis, carries its own lot code, and is tested by an independent third-party lab. The COA for your lot is available by email on request.

The 100mg vial is not a more concentrated product. It holds twice the material.

Why GHK-Cu is blue.

GHK-Cu is blue, and researchers new to it often ask why. The colour comes from the bound copper, not from the peptide chain.

When copper(II) is bound by GHK, the complex absorbs visible light. A 2021 spectroscopy study of the Cu(II)–GHK complex places its main visible absorption band (a copper d–d band) near 600 nm, in the orange-red part of the spectrum. Absorbing orange-red light leaves blue as the colour you see. Copper peptide formulations are plainly blue, and the depth of the hue tracks how much copper peptide is present.

Two practical points follow. First, both vial sizes should show the same colour, since the compound is identical; a stronger or paler shade in solution reflects concentration, not a different product. Second, colour is not a quality test. It indicates copper is present. It says nothing about purity or identity, which is what the purity and identity results on the COA are for.

What's different: cost per mg.

The 100mg vial is $84.99 and the 50mg vial is $54.99. That works out to $0.85 per mg against $1.10 per mg, so each milligram costs about 23% less in the larger vial.

On equal material the gap is clearer. If your work needs 100mg, one 100mg vial is $84.99 and two 50mg vials are $109.98. The larger vial saves $24.99 on the same amount of peptide.

What's different: the storage window.

Sealed vials of either size are stored the same way, at 2–8°C and away from light. Vitaliti's stated window for a reconstituted vial is up to 30 days refrigerated, and the GHK-Cu product page states the same window. The same general point holds for all peptides: a peptide in solution has a much shorter shelf life than the dry powder.

That makes the choice about timing, not just price. If your work will use all 100mg inside one window, the larger vial gives the same material for less. If it will not, what is left after the window is lost. Using only half of a 100mg vial means the material you actually used cost $1.70 per mg, more than the 50mg vial's $1.10.

Two 50mg vials let you open one and keep the other sealed until needed.

Documentation.

Each vial is labelled with its lot code and expiration date. Vials from different orders may come from different lots, and each lot has its own COA. Request the COA for your exact lot at contact@vitalitipeptide.com.

Which to choose.

The line sits at 50mg per window. Above it, one 100mg vial ($84.99) costs less than two 50mg vials ($109.98) even if part of it goes unused. At or below it, the 50mg vial avoids paying for material that will pass its window.