A GHK-Cu certificate can report the amount of complex and a copper-to-peptide ratio. Read those entries separately: milligrams of complex are not milligrams of elemental copper.
Match the complex and report
The supplied 50 mg GHK-Cu example is report MA-GHK-0001, revision 01, lot GHK-01-5Q2. It describes a lyophilised copper(II) tripeptide complex with sequence GHK and an LC-HRMS identity conclusion against a reference. These are the document’s descriptions, not an independent structural determination.GHK-Cu report (PDF) (opens in a new tab)
Read the measurements together
| Measurement | Result | Stated requirement |
|---|---|---|
| Complex purity (area) | 99.18% | ≥99.00% |
| Complex per vial | 49.90 mg | 45.00–55.00 mg |
| Cu:peptide molar ratio | 1.00 mol/mol | 0.95–1.05 mol/mol |
| Water content | 3.70% | ≤8.00% |
The report associates purity and complex content with HPLC-UV, and the copper-to-peptide ratio with ICP-OES. The 49.90 mg entry is reported as complex content; it should not be relabelled as elemental copper or free GHK. Dividing by the 50 mg label claim gives 99.8% of that claim, a separate arithmetic comparison from 99.18% area purity.GHK-Cu report (PDF) (opens in a new tab)
Preserve the ratio basis
A 1.00 mol/mol ratio describes equal amounts of substance in the ratio, not equal masses. Ask how the copper numerator and peptide denominator were established, and which corrections or uncertainty apply. The summary does not show every calculation step, so the instrument acronym alone leaves those questions open.GHK-Cu report (PDF) (opens in a new tab)BIPM — The International System of Units (opens in a new tab)
An elemental copper measurement alone does not allocate all measured copper to a particular peptide complex. Keep the reported copper-to-peptide ratio alongside the identity and related-species evidence, and ask which chemical forms the analytical work distinguished.GHK-Cu report (PDF) (opens in a new tab)Noormägi et al. (2023) (opens in a new tab)
The report lists a main peak at 11.50 minutes and assigns related entries to uncomplexed peptide and a copper-deficient species. Those are reported assignments; the trace image alone is not a separate confirmation. Its 0.82% total related-substances result remains a distinct entry from the ratio.GHK-Cu report (PDF) (opens in a new tab)
For a focused enquiry, quote the lot, exact assay label, ratio units and unclear calculation basis. Keep the report’s wording intact until the issuer supplies clarification.GHK-Cu report (PDF) (opens in a new tab)
Sources and further detail
- Supplied GHK-Cu 50 mg certificate (opens in a new tab)
MA-GHK-0001, revision 01; task URDL5Q2; lot GHK-01-5Q2. Source of the complex, content and ratio examples. The cited PDF was re-read on 3 October 2026 to check this transcription; its issuer and findings were not independently authenticated.
- BIPM — The International System of Units (opens in a new tab)
Ninth edition, English version 4.01 (2026), tables 7 and 8 and section 5.4.7. Definitions and notation; examples in this article are independently constructed.
- Noormägi et al. (2023), DOI 10.1021/acsomega.3c04649 (opens in a new tab)
Existing copper-quantification dossier source, used only for the distinction between an elemental measurement and species-resolved analysis. Study-specific comparisons are not transferred to GHK-Cu.
Revised from the existing source dossier on 3 October 2026. Supplied-report values are document transcriptions, not independent authentication or new measurements. Source notes identify the scope of each reference; this article has not undergone independent scientific peer review.