AssayIndex

AX-2026-042716

GHK-Cu · 50 mg declared · Shanghai ERP Biotechnology Co., Ltd. · lot ERP-2601-F9816

MARGINALPARTIAL
Report ID
AX-2026-042716
Compound
GHK-Cu
Compound class
Tissue-repair and immunomodulatory peptides
Supplier
ERP — Shanghai ERP Biotechnology Co., Ltd.
Batch / lot
ERP-2601-F9816
Declared label claim
50mg
Laboratory
PeptideMeter
Assay date
22 May 2026
Submitted
05 Jun 2026
Quarter
2026-Q2
Submitter
ro.kimani
Sample provenance
Laboratory-retained
Section 1

Results

Measured against the index acceptance specification for the tissue-repair and immunomodulatory peptides class. A specification is a decision the index made; a result is a measurement. See where each threshold came from.

ParameterMethodResultUnitIndex spec
PurityRP-HPLC, 28 min gradient, 214 nm98.80% area≥ 97.0PASS
Total impuritiesRP-HPLC, sum of reported peaks1.20% area≤ 3.0PASS
Largest single impurityRP-HPLC — GHK-Cu 2:1 complex0.51% area≤ 1.00PASS
Identitynot ordered on this submissionnot determinedrequired for VERIFIED statusNOT TESTED
Total peptide contentby difference from the gravimetric mass balance95.23%w/wNOT TESTED
Target-compound contenttotal peptide content × purity94.09%w/wNOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen48.90mg50 mg declaredNOT TESTED
Recovered target peptidegross fill × target content46.010mg50 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim92.0%90.0 – 110.0PASS
Water contentKarl Fischer, coulometric, duplicate4.37%≤ 10.0PASS
Counter-ionno ionisable counter-ion expectedN/Anot applicableNOT TESTED
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.40%NOT TESTED
Endotoxinnot ordered on this submissionnot determined≤ 5.0NOT TESTED
Sterilitynot ordered on this submissionnot determinedno growthNOT TESTED
Appearancevisual, diffuse light, black and white backgroundWhite lyophilised cake, intactwhite to off-white intact cakePASS
Reconstitution clarityreconstituted per submitter procedureVisible particulates, did not clearclear, no visible particulatesFAIL
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration7.452.5 – 8.0PASS
Retention time (observed)RP-HPLC, 28 min gradient5.75min5.80 ± 0.25 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.460.970.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²62,554≥ 20,000PASS
Resolution to nearest impurityvs oxidised His (+16 Da)2.38no index criterionREPORTED
Section 2

Chromatogram and peak integration

The figure is drawn from the table. It is not an independent illustration — if a number in the table changed, the trace would change with it.

05050101011515120202 GHK-Cu5.75 min · 98.80 % 5.30 same trace · ×100 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 051015202530 Retention time (min) Response (mAU)
Figure 1. RP-HPLC trace, 28 min gradient, 214 nm. Drawn from the peak-integration table below: peak positions are the reported retention times, peak areas are the reported area percentages, peak widths follow the reported plate count of 62,554, and skew follows the reported asymmetry factor of 0.97. Baseline noise is seeded from the report ID and is illustrative. The lower panel is the same trace at a stated vertical expansion with the slow gradient drift subtracted, because at full scale a 0.51 % impurity against a 98.80 % main peak is a line two pixels tall; the main peak runs off-scale there by design.
#PeakRTArea (µV·s)% areaΔ mass (Da)
1GHK-Cu — main peak5.754,801,98698.80
2GHK-Cu 2:1 complex6.3324,7880.51+277.145
3apo-GHK (copper-free, −62 Da)5.3021,3850.44-61.930
4Gly-His dipeptide (−128 Da)5.107,7760.16-128.095
5oxidised His (+16 Da)5.534,3740.09+15.995
Closure check — purity + Σ impurities 100.00CLOSES

Reporting threshold 0.05 % area. Peaks below it are not reported and are therefore excluded from the total, which overstates purity by their sum — see peak integration.

Section 4

Gravimetric mass balance

Water, counter-ion, residual and total peptide content are exhaustive and mutually exclusive categories. They must account for 100 % of the cake mass. The index closes this to within 0.02 pp and the build asserts it.

ComponentDetermination%w/w of cake
WaterKarl Fischer4.37
Counter-ionnone expected0.00
Residual solvent + inorganic residueestimated0.40
Total peptide contentby difference95.23
Total100.00 CLOSES

Supplier certificate, as declared

The supplier's own figures for this lot, beside the independent measurement. Divergence is assessed against the batch median, not against this single report — see rule AX-R05.

FigureSupplier COAThis reportIndex note
Purity (% area)99.098.80divergence +0.35 pp vs batch median
Total impurities (% area)1.001.20
Largest single impurity (% area)0.390.51
Water (%)not stated4.37
Counter-ion (%)5.1N/A
Peptide content (%w/w)90.895.23
Endotoxin (EU/mg)not statednot determined
Method stated on certificateNOno method section — the result cannot be reconciled against any other
Section 5

Provenance and caveats

Where a sample came from changes the weight of the evidence. The index treats it as a first-class field.

Sample provenance
Laboratory-retained
Evidentiary weight
Provenance documented, selection uncontrolled.
Chain of custody
Laboratory retained sample (−20 °C, 22 d since original receipt) → re-assay.
Assay date
22 May 2026
Submitted to the index
05 Jun 2026
Laboratory
PeptideMeter, Tallinn, Estonia
Method basis
28 min gradient · high-resolution MS
Verification status
PARTIAL
Section 6

Annotations 2

Signed technical comments from index contributors. Not a discussion forum — annotations question or contextualise the result, and the data team replies where a reply is warranted.

coa_template
Two suppliers using the same certificate template usually share a contract laboratory. That is a supply-chain observation and it is more interesting than the rounding itself.
nmr_qnmr
Quantitative NMR would give absolute content independent of the balance and let the two be cross-checked. On a record like this the balance is already closed; the cross-check would test the assumption behind it.
Section 7

Related records

Same batch — lot ERP-2601-F9816 n=10

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042707ERP-2601-F9816Janoshik2026-Q298.534.7096.3Buyer-sourced1MARGINAL
AX-2026-042708ERP-2601-F9816Nordanalyt2026-Q298.883.8791.5Buyer-sourced1MARGINAL
AX-2026-042709ERP-2601-F9816PeptideMeter2026-Q298.653.9994.6Buyer-sourced1MARGINAL
AX-2026-042710ERP-2601-F9816Nordanalyt2026-Q298.654.2499.6Buyer-sourced1MARGINAL
AX-2026-042711ERP-2601-F9816Kestrel2026-Q298.533.8489.7Laboratory-retained2MARGINAL
AX-2026-042712ERP-2601-F9816PeptideMeter2026-Q298.483.08100.3Buyer-sourced1MARGINAL
AX-2026-042713ERP-2601-F9816VendorInvestigate2026-Q298.023.75Buyer-sourced2FAIL
AX-2026-042714ERP-2601-F9816Kestrel2026-Q298.934.31106.7Buyer-sourced2MARGINAL
AX-2026-042715ERP-2601-F9816Nordanalyt2026-Q298.653.9198.7Buyer-sourced1MARGINAL
Other recent GHK-Cu records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043160SSASSA-2604-V7731Janoshik2026-Q298.014.0291.8Buyer-sourced0PASS
AX-2026-043157SSASSA-2604-V7731Medutest2026-Q299.195.14Supplier-supplied0PASS
AX-2026-041251WWBWWB-2512-B1996PeptideMeter2026-Q299.435.87Buyer-sourced1MARGINAL
AX-2026-043249CPCCPC-2601-D1258Kestrel2026-Q299.506.96Supplier-supplied0PASS
AX-2026-043245CPCCPC-2601-D1258PeptideMeter2026-Q298.106.5795.0Supplier-supplied0PASS
AX-2026-041247WWBWWB-2512-B1996PeptideMeter2026-Q299.236.0988.8Buyer-sourced1MARGINAL
AX-2026-042708ERPERP-2601-F9816Nordanalyt2026-Q298.883.8791.5Buyer-sourced1MARGINAL
AX-2026-043154SSASSA-2604-V7731PeptideMeter2026-Q297.824.82101.6Buyer-sourced0PASS
Other recent ERP records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042706SurvodutideERP-2605-E9865PeptideMeter2026-Q398.385.33103.5Buyer-sourced0PASS
AX-2026-042704TesamorelinERP-2604-W9463Janoshik2026-Q399.024.08Buyer-sourced1MARGINAL
AX-2026-042705SurvodutideERP-2605-E9865Janoshik2026-Q398.245.3692.3Buyer-sourced0PASS
AX-2026-042708GHK-CuERP-2601-F9816Nordanalyt2026-Q298.883.8791.5Buyer-sourced1MARGINAL
AX-2026-042694LiraglutideERP-2601-P8985Kestrel2026-Q299.254.35107.3Buyer-sourced1MARGINAL
AX-2026-042707GHK-CuERP-2601-F9816Janoshik2026-Q298.534.7096.3Buyer-sourced1MARGINAL
AX-2026-042711GHK-CuERP-2601-F9816Kestrel2026-Q298.533.8489.7Laboratory-retained2MARGINAL
AX-2026-042722TirzepatideERP-2512-T9616Medutest2026-Q299.182.07Buyer-sourced1MARGINAL