AX-2025-019910 · PEG-MGF · HJ lot HJ-2507-S5943

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.

Parameter	Method	Result	Unit	Index spec
Purity	RP-HPLC, 25 min gradient, 214 nm	98.36	% area	≥ 92.0	PASS
Total impurities	RP-HPLC, sum of reported peaks	1.64	% area	≤ 8.0	PASS
Largest single impurity	RP-HPLC — hydrolysed linker	0.81	% area	≤ 1.00	PASS
Identity — theoretical monoisotopic mass	calculated from molecular formula	7894.0000	Da	—	NOT TESTED
Identity — observed monoisotopic mass	LC-MS, unit resolution (single quadrupole)	7894.1610	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	+20.4	ppm	± 15	FAIL
Peptide content	not ordered on this submission	not determined	—	required to check label claim	NOT TESTED
Water content	Karl Fischer, coulometric, duplicate	6.95	%	≤ 9.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	1.86	%	≤ 12.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.48	%	—	NOT TESTED
Endotoxin	not ordered on this submission	not determined	—	≤ 5.0	NOT TESTED
Sterility	not ordered on this submission	not determined	—	no growth	NOT TESTED
Appearance	visual, diffuse light, black and white background	Off-white lyophilised cake, intact	—	white to off-white intact cake	PASS
Reconstitution clarity	reconstituted per submitter procedure	Clear, colourless, no visible particulates	—	clear, no visible particulates	PASS
pH (reconstituted, 1 mg/mL)	potentiometric, two-point calibration	4.29	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 25 min gradient	14.59	min	14.60 ± 0.80 (normalised)	PASS
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	1.07	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	50,502	—	≥ 20,000	PASS
Resolution to nearest impurity	vs hydrolysed linker	2.25	—	no index criterion	REPORTED

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.

Figure 1. RP-HPLC trace, 25 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 50,502, and skew follows the reported asymmetry factor of 1.07. 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 0.81 % impurity against a 98.36 % main peak is a line two pixels tall; the main peak runs off-scale there by design.

#	Peak	RT	Area (µV·s)	% area	Δ mass (Da)
1	PEG-MGF — main peak	14.59	4,780,601	98.36	—
2	hydrolysed linker	13.99	39,369	0.81	+18.011
3	free MGF (unconjugated)	9.91	16,525	0.34	-5007.488
4	di-PEGylated species	16.13	13,123	0.27	+5000.000
5	free mPEG	16.61	10,693	0.22	-2886.512
Closure check — purity + Σ impurities				100.00	CLOSES

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 7894.0000 Da, computed from conjugate (24-mer + 5 kDa mPEG). All ppm figures on this site are against monoisotopic values — see why that matters.

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 7894.1610 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.

Charge	Theoretical m/z	Observed m/z	Δ m/z	Rel. abundance (%)
10+	790.4073	790.4234	0.0161	8.0
9+	878.1184	878.1363	0.0179	57.4
8+	987.7573	987.7774	0.0201	100.0
7+	1128.7216	1128.7446	0.0230	53.4
6+	1316.6739	1316.7008	0.0269	7.9

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.

Figure	Supplier COA	This report	Index note
Purity (% area)	98.07	98.36	divergence -0.09 pp vs batch median
Total impurities (% area)	1.93	1.64
Largest single impurity (% area)	not stated	0.81
Water (%)	5.3	6.95
Counter-ion (%)	not stated	1.86
Peptide content (%w/w)	not stated	not determined
Endotoxin (EU/mg)	0.21	not determined
Method stated on certificate	YES	—	column, 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 (−20 °C, 31 d) → laboratory (courier, dry ice, 5 d) → assay.
Assay date: 18 Jul 2025
Submitted to the index: 27 Jul 2025
Laboratory: Medutest, Ljubljana, Slovenia
Method basis: 25 min gradient · unit-resolution MS
Verification status: IDENTITY CONSISTENT

What this report does not establish

That the compound is not a near-isobaric alternative. Identity was confirmed at unit mass resolution, which cannot exclude species differing by 1 or 2 Da. The specific alternatives not excluded are named in the identity block above.
How much of the named compound is in the vial. Peptide content was not determined, so recovered mass cannot be calculated and the label claim cannot be checked.
That the material is free of bacterial endotoxin. Endotoxin was not measured. No chromatographic result bears on it.
That the material is sterile. Sterility was not tested.
That any other vial in the same lot has the same composition. One vial was tested. Within-lot vial-to-vial variation in this index has a median of 0.28 pp and a 90th percentile of 0.74 pp.
That any other lot from the same supplier has the same composition. Batch-to-batch variation is larger than within-batch variation for every supplier here.
That the material is suitable for administration to a human or an animal. These are research compounds. No result on this site is a safety assessment and the index takes no position on use.
That the material was manufactured by the supplier that sold it. Contract synthesis is normal in this market and twenty-nine batches in the index fingerprint to a bulk from a different company than the one named on the label.

Section 6

Annotations 4

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.

ms_confirm27 Jul 2025

Identity confirmation needs a reference standard and the record does not say whose was used. Where the deviation is small this is the first ambiguity to remove.

buyer_sourced27 Jul 2025

Buyer-sourced through an ordinary retail order, so the supplier had no opportunity to select the vial. This is the provenance class the index weights and it is roughly 87 % of the dataset.

price_per_mg27 Jul 2025

A retail purchase carries a price, which makes cost per milligram of recovered peptide computable. That is the comparison a buyer actually needs and it exists only for this provenance class.

sample_vs_retail27 Jul 2025

Anyone can generate one of these. That is the argument the index makes on its submission page and it is the reason the dataset grows without any supplier's cooperation.

Section 7

Related records

Same batch — lot HJ-2507-S5943 n=9

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Result
AX-2025-019906	HJ-2507-S5943	Kestrel	2025-Q3	98.54	7.23	—	Buyer-sourced	PASS
AX-2025-019907	HJ-2507-S5943	Janoshik	2025-Q3	98.20	6.75	—	Buyer-sourced	PASS
AX-2025-019908	HJ-2507-S5943	Janoshik	2025-Q3	98.16	7.25	104.1	Buyer-sourced	PASS
AX-2025-019909	HJ-2507-S5943	Janoshik	2025-Q3	97.65	7.04	—	Buyer-sourced	PASS
AX-2025-019911	HJ-2507-S5943	Janoshik	2025-Q3	97.65	7.07	91.8	Buyer-sourced	PASS
AX-2025-019912	HJ-2507-S5943	Janoshik	2025-Q3	97.70	7.08	—	Buyer-sourced	PASS
AX-2025-019913	HJ-2507-S5943	Nordanalyt	2025-Q3	98.33	6.64	—	Buyer-sourced	PASS
AX-2025-019914	HJ-2507-S5943	Medutest	2025-Q3	98.14	7.59	—	Buyer-sourced	PASS

Batch rollup and reproducibility assessment →

Cross-sections

Other recent PEG-MGF records in the index.
Report	Supplier	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041821	ASY	ASY-{CAT}-2379	Janoshik	2026-Q2	98.57	5.79	95.3	Buyer-sourced	0	PASS
AX-2026-043577	SIG	SIG-2602-6794	Kestrel	2026-Q2	97.66	6.08	—	Buyer-sourced	0	PASS
AX-2026-043570	SIG	SIG-2602-6794	PeptideMeter	2026-Q2	97.76	5.45	104.2	Buyer-sourced	0	PASS
AX-2026-043569	SIG	SIG-2602-6794	PeptideMeter	2026-Q2	97.52	5.36	—	Laboratory-retained	0	PASS
AX-2026-043573	SIG	SIG-2602-6794	Janoshik	2026-Q2	98.58	4.79	104.2	Buyer-sourced	0	PASS
AX-2026-041822	ASY	ASY-{CAT}-2379	Janoshik	2026-Q2	98.83	6.51	—	Laboratory-retained	0	PASS
AX-2026-043574	SIG	SIG-2602-6794	Kestrel	2026-Q2	98.04	5.98	88.6	Buyer-sourced	1	MARGINAL
AX-2026-043576	SIG	SIG-2602-6794	Nordanalyt	2026-Q2	97.61	5.56	—	Buyer-sourced	0	PASS

Other recent HJ records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-042595	Semaglutide	HJ-2608-C7002	Janoshik	2026-Q3	99.50	3.55	—	Buyer-sourced	1	MARGINAL
AX-2026-042598	Semaglutide	HJ-2608-C7002	Janoshik	2026-Q3	99.59	3.84	—	Buyer-sourced	0	PASS
AX-2026-042605	Semaglutide	HJ-2608-C7002	Janoshik	2026-Q3	99.03	3.37	107.3	Buyer-sourced	0	PASS
AX-2026-042602	Semaglutide	HJ-2608-C7002	Nordanalyt	2026-Q3	99.21	3.50	92.0	Buyer-sourced	0	PASS
AX-2026-042603	Semaglutide	HJ-2608-C7002	Janoshik	2026-Q3	99.16	3.42	105.9	Buyer-sourced	0	PASS
AX-2026-042528	GHRP-6	HJ-2603-R5329	VendorInvestigate	2026-Q3	98.69	1.87	95.8	Buyer-sourced	0	FAIL
AX-2026-042526	GHRP-6	HJ-2603-R5329	Medutest	2026-Q3	99.37	3.06	—	Laboratory-retained	0	PASS
AX-2026-042527	GHRP-6	HJ-2603-R5329	VendorInvestigate	2026-Q3	99.21	2.77	93.2	Buyer-sourced	0	PASS