AssayIndex

AX-2025-020270

MGF · 2 mg declared · Nantong Guangyuan Chemical Co., Ltd. · lot GGPE-2506-T1988

MARGINALVERIFIED
Report ID
AX-2025-020270
Compound
MGF
Compound class
Growth-hormone axis peptides
Supplier
GGPeps — Nantong Guangyuan Chemical Co., Ltd.
Batch / lot
GGPE-2506-T1988
Declared label claim
2mg
Laboratory
VendorInvestigate
Assay date
26 Nov 2025
Submitted
02 Dec 2025
Quarter
2025-Q4
Submitter
p.petrov
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, 32 min gradient, 214 nm98.57% area≥ 97.5PASS
Total impuritiesRP-HPLC, sum of reported peaks1.43% area≤ 2.5PASS
Largest single impurityRP-HPLC — deamidated (+1 Da)0.89% area≤ 1.00PASS
Identity — theoretical monoisotopic masscalculated from molecular formula2886.5117DaNOT TESTED
Identity — observed monoisotopic massLC-MS, high resolution (ESI-TOF/QTOF)2886.5071DaNOT TESTED
Mass accuracyobserved vs theoretical-1.6ppm± 15PASS
Total peptide contentby difference from the gravimetric mass balance91.21%w/wNOT TESTED
Target-compound contenttotal peptide content × purity89.91%w/wNOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen1.97mg2 mg declaredNOT TESTED
Recovered target peptidegross fill × target content1.771mg2 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim88.6%90.0 – 110.0FAIL
Water contentKarl Fischer, coulometric, duplicate4.34%≤ 9.0PASS
Counter-ion (acetate)anion-exchange ion chromatography3.73%≤ 12.0PASS
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.72%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 procedureClear, colourless, no visible particulatesclear, no visible particulatesPASS
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration5.332.5 – 8.0PASS
Retention time (observed)RP-HPLC, 32 min gradient12.32min12.33 ± 0.30 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.460.920.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²59,817≥ 20,000PASS
Resolution to nearest impurityvs deamidated (+1 Da)1.24no 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.

02359471970789438 MGF12.32 min · 98.57 % 12.06 same trace · ×50 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 05101520253035 Retention time (min) Response (mAU)
Figure 1. RP-HPLC trace, 32 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 59,817, and skew follows the reported asymmetry factor of 0.92. 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 0.89 % impurity against a 98.57 % main peak is a line two pixels tall; the main peak runs off-scale there by design.
#PeakRTArea (µV·s)% areaΔ mass (Da)
1MGF — main peak12.324,790,80898.57
2deamidated (+1 Da)12.0643,2570.89+0.984
3aspartimide (−18 Da)12.6617,9830.37-18.011
4truncated (1-20)11.024,8600.10-486.271
5acetyl adduct (+42 Da)12.753,4020.07+42.011
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 2886.5117 Da, computed from C121H200N42O37. All ppm figures on this site are against monoisotopic values — see why that matters.

0255075100450650850105012501450 [M+3H]3+963.18[M+4H]4+722.63[M+2H]2+1444.26 m/z Relative abundance (%)
Figure 2. ESI charge-state envelope, high-resolution instrument. Sticks are placed at m/z = (M + z × 1.007276)/z for the observed neutral mass of 2886.5071 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 (%)
5+578.3096578.3087-0.00097.6
4+722.6352722.6341-0.001157.5
3+963.1778963.1763-0.0015100.0
2+1444.26311444.2608-0.002353.7
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 Fischer4.34
Counter-ion (acetate)ion chromatography3.73
Residual solvent + inorganic residueestimated0.72
Total peptide contentby difference91.21
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)98.2998.57divergence -0.20 pp vs batch median
Total impurities (% area)1.711.43
Largest single impurity (% area)0.920.89
Water (%)3.64.34
Counter-ion (%)not stated3.73
Peptide content (%w/w)91.691.21
Endotoxin (EU/mg)not statednot determined
Method stated on certificateYEScolumn, gradient and wavelength given
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 → submitter (ambient, 30 d) → laboratory (courier, cold pack, 4 d) → assay.
Assay date
26 Nov 2025
Submitted to the index
02 Dec 2025
Laboratory
VendorInvestigate, Riga, Latvia
Method basis
32 min gradient · high-resolution MS
Verification status
VERIFIED
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.

hplc_ola
Column temperature shifts selectivity by a few percent per ten degrees on peptides. Where two peaks are this close that is enough to matter and it is rarely on the report.
hilic_hana
Orthogonal selectivity solves what more of the same selectivity does not. HILIC on a pair that co-elutes on C18 frequently resolves it outright.
label_claim
1.77 mg recovered against a 2 mg claim is 88.6 %. Three contributions: purity at 98.57 %, content at 89.91 %w/w and water at 4.34 %. Content is doing most of the work, as it usually is.
Section 7

Related records

Same batch — lot GGPE-2506-T1988 n=4

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2025-020268GGPE-2506-T1988PeptideMeter2025-Q498.024.30101.5Buyer-sourced0PASS
AX-2025-020269GGPE-2506-T1988Medutest2025-Q498.704.2096.4Supplier-supplied1FAIL
AX-2025-020271GGPE-2506-T1988Nordanalyt2025-Q498.404.76Buyer-sourced0PASS
Other recent MGF records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043660PPGPPG-2512-G7713Janoshik2026-Q299.304.2595.8Buyer-sourced0PASS
AX-2026-043656PPGPPG-2512-G7713PeptideMeter2026-Q299.094.2299.3Buyer-sourced0PASS
AX-2026-043657PPGPPG-2512-G7713Janoshik2026-Q299.064.25107.0Buyer-sourced0PASS
AX-2026-043466BCHBCH-2511-D5168Janoshik2026-Q299.045.33103.5Buyer-sourced0PASS
AX-2026-043464BCHBCH-2511-D5168VendorInvestigate2026-Q299.395.79100.2Buyer-sourced0PASS
AX-2026-043655PPGPPG-2512-G7713Medutest2026-Q299.034.1499.6Buyer-sourced0PASS
AX-2026-043467BCHBCH-2511-D5168Janoshik2026-Q299.465.95Supplier-supplied0PASS
AX-2026-043652PPGPPG-2512-G7713Janoshik2026-Q299.333.87101.6Buyer-sourced0PASS
Other recent GGPeps records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042784CJC-1295 (no DAC)GGPE-2606-E1234Medutest2026-Q398.274.55Buyer-sourced0PASS
AX-2026-042786CJC-1295 (no DAC)GGPE-2606-E1234Janoshik2026-Q398.223.77Buyer-sourced0PASS
AX-2026-042858SelankGGPE-2603-J2447VendorInvestigate2026-Q398.878.8599.4Buyer-sourced0FAIL
AX-2026-042783CJC-1295 (no DAC)GGPE-2606-E1234Janoshik2026-Q398.224.4590.6Buyer-sourced0PASS
AX-2026-042757Melanotan IIGGPE-2603-P1474Janoshik2026-Q399.546.7892.0Buyer-sourced0PASS
AX-2026-042785CJC-1295 (no DAC)GGPE-2606-E1234PeptideMeter2026-Q397.704.6491.4Buyer-sourced0FAIL
AX-2026-042756Melanotan IIGGPE-2603-P1474Nordanalyt2026-Q399.177.04Buyer-sourced0PASS
AX-2026-042755Melanotan IIGGPE-2603-P1474Nordanalyt2026-Q399.256.5890.4Buyer-sourced0PASS