AssayIndex

AX-2026-042711

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

MARGINALPARTIAL
Report ID
AX-2026-042711
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
Kestrel Bioanalytical
Assay date
04 Jun 2026
Submitted
11 Jun 2026
Quarter
2026-Q2
Submitter
same_trace_twice
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, 15 min gradient, 214 nm98.53% area≥ 97.0PASS
Total impuritiesRP-HPLC, sum of reported peaks1.47% area≤ 3.0PASS
Largest single impurityRP-HPLC — GHK-Cu 2:1 complex0.62% area≤ 1.00PASS
Identitynot ordered on this submissionnot determinedrequired for VERIFIED statusNOT TESTED
Total peptide contentby difference from the gravimetric mass balance95.70%w/wNOT TESTED
Target-compound contenttotal peptide content × purity94.29%w/wNOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen47.54mg50 mg declaredNOT TESTED
Recovered target peptidegross fill × target content44.825mg50 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim89.7%90.0 – 110.0FAIL
Water contentKarl Fischer, coulometric, duplicate3.84%≤ 10.0PASS
Counter-ionno ionisable counter-ion expectedN/Anot applicableNOT TESTED
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.46%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 cake, partial shrinkage from vial wallwhite to off-white intact cakeFAIL
Reconstitution clarityreconstituted per submitter procedureClear, colourless, no visible particulatesclear, no visible particulatesPASS
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration7.082.5 – 8.0PASS
Retention time (observed)RP-HPLC, 15 min gradient3.19min3.34 ± 0.25 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.461.170.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²79,710≥ 20,000PASS
Resolution to nearest impurityvs oxidised His (+16 Da)2.59no 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.

09304186072791137214 GHK-Cu3.19 min · 98.53 % 3.50 same trace · ×100 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 048121620 Retention time (min) Response (mAU)
Figure 1. RP-HPLC trace, 15 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 79,710, and skew follows the reported asymmetry factor of 1.17. 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 0.62 % impurity against a 98.53 % 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 peak3.194,788,86398.53
2GHK-Cu 2:1 complex3.5030,1340.62+277.145
3oxidised His (+16 Da)3.0725,2740.52+15.995
4Gly-His dipeptide (−128 Da)2.849,2350.19-128.095
5apo-GHK (copper-free, −62 Da)2.956,8040.14-61.930
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 Fischer3.84
Counter-ionnone expected0.00
Residual solvent + inorganic residueestimated0.46
Total peptide contentby difference95.70
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)99.098.53divergence +0.35 pp vs batch median
Total impurities (% area)1.001.47
Largest single impurity (% area)0.390.62
Water (%)not stated3.84
Counter-ion (%)5.1N/A
Peptide content (%w/w)90.895.70
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, 7 d since original receipt) → re-assay.
Assay date
04 Jun 2026
Submitted to the index
11 Jun 2026
Laboratory
Kestrel Bioanalytical, Melbourne, Australia
Method basis
15 min gradient · unit-resolution MS
Verification status
PARTIAL
Section 6

Annotations 3

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.

digit_preference
A supplier that reports 98.5 and 99.0 across a catalogue is quantising. A supplier that reports 98.5 on every lot of every compound would be doing something else, and that pattern does not occur in this index.
underfill_3to1
Automated filling on a low-mass vial has a real tolerance and it is wider than most labels imply. A ±10 % index tolerance is generous against pharmacopoeial content uniformity and this record sits outside even that.
coa_reader
The certificate field that would settle this in one line is the content basis. Anhydrous and salt-free, as-is, or gross: three different numbers and one field.
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-2026-042712ERP-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
AX-2026-042716ERP-2601-F9816PeptideMeter2026-Q298.804.3792.0Laboratory-retained1MARGINAL
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-2026-042722TirzepatideERP-2512-T9616Medutest2026-Q299.182.07Buyer-sourced1MARGINAL
AX-2026-042715GHK-CuERP-2601-F9816Nordanalyt2026-Q298.653.9198.7Buyer-sourced1MARGINAL