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Custom · copper coordinated by the glutathione tripeptide
Overview
The Copper-Glutathione complex is a made-to-order copper coordination active in which the metal is carried by glutathione — the γ-glutamyl-cysteinyl-glycine tripeptide. It belongs in Cupratec's coordination range as a distinct copper-binding motif: the coordination literature documents copper-glutathione complexes in detail, with Cu(II) coordinated through the amino nitrogens and carboxyl oxygens of the γ-glutamyl residues, and a well-studied Cu(I)/Cu(II) chemistry that is central to how glutathione handles copper in solution. That redox-active copper-thiol-peptide behaviour is exactly what distinguishes it from the histidine-anchored GHK complexes and makes it interesting to a coordination-chemistry buyer. As with copper-carnosine, there is no single standardised cosmetic catalogue identifier for a copper-glutathione complex — its identity depends on copper-to-ligand stoichiometry, oxidation state, and formation conditions — so Cupratec supplies it as a custom synthesis and records the measured copper content, the copper-to-glutathione ratio as-found, and the characterisation figures on the batch COA. Cupratec supplies it strictly as a cosmetic active; efficacy and any cosmetic claim a finished product makes are the brand's responsibility under its destination-market rules. This is a custom, made-to-order active from the Cu-peptide programme — from 25 g pilot scale through release. Because glutathione carries a free thiol and a redox-active copper chemistry, the scoping conversation covers oxidation state and handling explicitly alongside the target copper-to-glutathione stoichiometry and carrier chemistry, and the release file is built around what was actually made. Each commissioned lot carries a measured copper-content figure by atomic absorption with the copper-to-glutathione relationship reported as-found, reversed-phase HPLC and identity confirmation, and a UV-Vis read characterising the complex for the lot. Because there is no standard catalogue CAS, the COA is the identity record and the spectral signature is logged against an internal Copper-Glutathione reference rather than the GHK-Cu band near 622 nm. Lead time is quoted per project. The copper-coordination and lot-release logic is the same as for the peptide actives — see our Cu²⁺ : peptide ratio field note.
Who buys this, and why
Cosmetic-peptide buyers fall into two groups: established beauty / med-aesthetic brands extending an existing line, and private-label clients building a catalog from scratch. The first group usually wants lyophilized peptide material plus stability data in their existing carrier matrix; the second usually wants a finished formulation under their label. Both need INCI naming verified, regulator-specific safety files (CPNP for EU, FDA OTC monograph for US where relevant), and packaging-compatibility data.
Primary buyer fit: regional distributors and re-sellers and academic and contract research laboratories.
Specifications
Documentation available on request
Regulatory note
Custom · made to order · from 25 g pilot scale. The Copper-Glutathione complex is a custom-synthesised copper-peptide coordination active; it is not assigned a fixed catalogue CAS or MW — copper content, the copper-to-glutathione ratio, oxidation-state handling, and characterisation are specified on the batch COA. Supplied as a cosmetic active only, not for compounded human-use preparations. Finished-product cosmetic claims are the brand's to substantiate under its destination-market rules.
Frequently asked questions
Because its identity depends on variables that no single cosmetic CAS captures: the copper-to-ligand stoichiometry, the copper oxidation state, and the conditions under which the complex is formed. The coordination chemistry is well documented — Cu(II) binds glutathione through the amino nitrogens and carboxyl oxygens of the γ-glutamyl residues, and the system has a much-studied Cu(I)/Cu(II) redox behaviour — but that same redox activity is why a single fixed identifier would misrepresent the material. Cupratec therefore runs it as a custom synthesis and records the measured copper content and the copper-to-glutathione ratio as-found on the batch COA, which is the honest identity record for the lot produced.
The binding motif and the redox behaviour are different. GHK-Cu and Copper-Carnosine anchor Cu(II) at a histidine imidazole; glutathione has no histidine and instead coordinates copper through the γ-glutamyl amino nitrogens and carboxyl oxygens, with a free cysteine thiol that drives a redox-active Cu(I)/Cu(II) chemistry not seen in the histidine complexes. For a coordination-chemistry buyer that makes it a genuinely distinct copper carrier — a copper-thiol-peptide motif rather than a copper-histidine one — which is why it earns its own entry in the range rather than being treated as another GHK-type complex. It is positioned for formulators and chemistry groups exploring that specific copper-glutathione coordination, not as a finished-product claim.
Because glutathione carries a free thiol and the copper chemistry is redox-active, Cupratec scopes oxidation state and handling explicitly alongside the target copper-to-glutathione stoichiometry, the carrier chemistry, and the documentation your QC group needs. It runs at 25 g pilot scale first, with the release file — a copper-content figure by atomic absorption with the copper-to-glutathione relationship as-found, reversed-phase HPLC and identity confirmation, and a UV-Vis read characterising the complex — built around what was actually produced. Scale-up follows once the pilot lot is qualified, and lead time is quoted per project. The lot-release discipline is the one described in our Cu²⁺ : peptide ratio field note.
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