AssayIndex

AX-2026-043538

GHRP-2 · 5 mg declared · Sigma-Aldrich (Shanghai) Trading Co., Ltd. · lot SIG-2603-6031

FAILIDENTITY CONSISTENT
Report ID
AX-2026-043538
Compound
GHRP-2
Compound class
Growth-hormone axis peptides
Supplier
SIG — Sigma-Aldrich (Shanghai) Trading Co., Ltd.
Batch / lot
SIG-2603-6031
Declared label claim
5mg
Laboratory
Kestrel Bioanalytical
Assay date
09 Aug 2026
Submitted
19 Aug 2026
Quarter
2026-Q3
Submitter
a.sandvik
Sample provenance
Buyer-sourced
Section 1

Results

Measured against the index acceptance specification for the growth-hormone axis 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 nm98.93% area≥ 99.0FAIL
Total impuritiesRP-HPLC, sum of reported peaks1.07% area≤ 1.0FAIL
Largest single impurityRP-HPLC — oxidised Trp (+16 Da)0.47% area≤ 1.00PASS
Identity — theoretical monoisotopic masscalculated from molecular formula817.4275DaNOT TESTED
Identity — observed monoisotopic massLC-MS, unit resolution (single quadrupole)817.4385DaNOT TESTED
Mass accuracyobserved vs theoretical+13.5ppm± 15PASS
Peptide contentnot ordered on this submissionnot determinedrequired to check label claimNOT TESTED
Water contentKarl Fischer, coulometric, duplicate1.72%≤ 9.0PASS
Counter-ion (acetate)anion-exchange ion chromatography7.47%≤ 12.0PASS
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.38%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, partially collapsedwhite to off-white intact cakeFAIL
Reconstitution clarityreconstituted per submitter procedureFaint haze, clearing on standingclear, no visible particulatesFAIL
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration5.012.5 – 8.0PASS
Retention time (observed)RP-HPLC, 15 min gradient4.84min4.89 ± 0.25 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.461.040.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²52,594≥ 20,000PASS
Resolution to nearest impurityvs [D-2-Nal]-epimer0.81no 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.

05320106401596021280 GHRP-24.84 min · 98.93 % 4.66 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 52,594, and skew follows the reported asymmetry factor of 1.04. 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 0.47 % impurity against a 98.93 % main peak is a line two pixels tall; the main peak runs off-scale there by design.
#PeakRTArea (µV·s)% areaΔ mass (Da)
1GHRP-2 — main peak4.844,808,30598.93
2oxidised Trp (+16 Da)4.6622,8430.47+15.995
3[D-2-Nal]-epimer4.7717,9830.370.000
4C-terminal free acid (+1 Da)4.926,3180.13+0.984
5des-Lys (−128 Da)4.724,8600.10-128.095
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 3

Mass spectrum and identity

Theoretical monoisotopic mass 817.4275 Da, computed from C45H55N9O6. All ppm figures on this site are against monoisotopic values — see why that matters.

0255075100350450550650750850 [M+1H]1+818.45[M+2H]2+409.73 m/z Relative abundance (%)
Figure 2. ESI charge-state envelope, unit-resolution instrument. Sticks are placed at m/z = (M + z × 1.007276)/z for the observed neutral mass of 817.4385 Da. Sodium (+21.982/z) and potassium (+37.956/z) adducts are shown where the parent charge state exceeds 25 % relative abundance; they are adducts of the same molecule and are not impurities.
ChargeTheoretical m/zObserved m/zΔ m/zRel. abundance (%)
2+409.7210409.72650.005557.6
1+818.4348818.44580.0110100.0
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.

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)98.8998.93divergence -0.22 pp vs batch median
Total impurities (% area)1.111.07
Largest single impurity (% area)not stated0.47
Water (%)0.91.72
Counter-ion (%)not stated7.47
Peptide content (%w/w)not statednot determined
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
Buyer-sourced
Evidentiary weight
Strongest available evidence in this index.
Chain of custody
Retail purchase → third-party forwarder (25 d) → laboratory (courier, cold pack, 9 d) → assay.
Assay date
09 Aug 2026
Submitted to the index
19 Aug 2026
Laboratory
Kestrel Bioanalytical, Melbourne, Australia
Method basis
15 min gradient · unit-resolution MS
Verification status
IDENTITY CONSISTENT
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.

lipidation_step
On an acylated compound the mono-ester by-product of the side-chain step is the impurity that most often carries a result into this band, and it is regiochemistry rather than sloppiness. The named table above will say whether that is what happened here.
dedupe_logic
Two retail purchases of the same lot from different buyers are genuinely independent. Two aliquots of one purchase are not, and the index does not treat them as such.
Section 7

Related records

Same batch — lot SIG-2603-6031 n=13

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043532SIG-2603-6031PeptideMeter2026-Q399.241.24Buyer-sourced0PASS
AX-2026-043533SIG-2603-6031Janoshik2026-Q398.511.1392.1Buyer-sourced0FAIL
AX-2026-043534SIG-2603-6031Medutest2026-Q399.112.1589.8Buyer-sourced1MARGINAL
AX-2026-043535SIG-2603-6031Janoshik2026-Q399.121.26105.7Buyer-sourced0PASS
AX-2026-043536SIG-2603-6031Medutest2026-Q399.171.41Buyer-sourced0PASS
AX-2026-043537SIG-2603-6031Janoshik2026-Q399.312.16Buyer-sourced0PASS
AX-2026-043539SIG-2603-6031Janoshik2026-Q398.951.74100.4Buyer-sourced1FAIL
AX-2026-043540SIG-2603-6031PeptideMeter2026-Q398.601.36Buyer-sourced1FAIL
AX-2026-043541SIG-2603-6031PeptideMeter2026-Q399.062.08107.4Buyer-sourced1MARGINAL
AX-2026-043542SIG-2603-6031VendorInvestigate2026-Q399.051.43Buyer-sourced1FAIL
AX-2026-043543SIG-2603-6031Janoshik2026-Q399.381.7098.6Buyer-sourced0PASS
AX-2026-043544SIG-2603-6031PeptideMeter2026-Q399.571.51105.4Buyer-sourced0PASS
Other recent GHRP-2 records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043535SIGSIG-2603-6031Janoshik2026-Q399.121.26105.7Buyer-sourced0PASS
AX-2026-043541SIGSIG-2603-6031PeptideMeter2026-Q399.062.08107.4Buyer-sourced1MARGINAL
AX-2026-043539SIGSIG-2603-6031Janoshik2026-Q398.951.74100.4Buyer-sourced1FAIL
AX-2026-043534SIGSIG-2603-6031Medutest2026-Q399.112.1589.8Buyer-sourced1MARGINAL
AX-2026-043542SIGSIG-2603-6031VendorInvestigate2026-Q399.051.43Buyer-sourced1FAIL
AX-2026-043543SIGSIG-2603-6031Janoshik2026-Q399.381.7098.6Buyer-sourced0PASS
AX-2026-043544SIGSIG-2603-6031PeptideMeter2026-Q399.571.51105.4Buyer-sourced0PASS
AX-2026-043536SIGSIG-2603-6031Medutest2026-Q399.171.41Buyer-sourced0PASS
Other recent SIG records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043535GHRP-2SIG-2603-6031Janoshik2026-Q399.121.26105.7Buyer-sourced0PASS
AX-2026-043541GHRP-2SIG-2603-6031PeptideMeter2026-Q399.062.08107.4Buyer-sourced1MARGINAL
AX-2026-043539GHRP-2SIG-2603-6031Janoshik2026-Q398.951.74100.4Buyer-sourced1FAIL
AX-2026-043534GHRP-2SIG-2603-6031Medutest2026-Q399.112.1589.8Buyer-sourced1MARGINAL
AX-2026-043542GHRP-2SIG-2603-6031VendorInvestigate2026-Q399.051.43Buyer-sourced1FAIL
AX-2026-043543GHRP-2SIG-2603-6031Janoshik2026-Q399.381.7098.6Buyer-sourced0PASS
AX-2026-043544GHRP-2SIG-2603-6031PeptideMeter2026-Q399.571.51105.4Buyer-sourced0PASS
AX-2026-043536GHRP-2SIG-2603-6031Medutest2026-Q399.171.41Buyer-sourced0PASS