AX-2024-004431 · Melanotan II · QSC lot QSC-2402-G9476

Section 1

Results

Measured against the index acceptance specification for the melanocortin-receptor 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, 30 min gradient, 214 nm	99.93	% area	≥ 98.5	PASS
Total impurities	RP-HPLC, sum of reported peaks	0.07	% area	≤ 1.5	PASS
Largest single impurity	RP-HPLC — des-acetyl MT-II (−42 Da)	0.04	% area	≤ 1.00	PASS
Identity	not ordered on this submission	not determined	—	required for VERIFIED status	NOT TESTED
Peptide content	not ordered on this submission	not determined	—	required to check label claim	NOT TESTED
Water content	Karl Fischer, coulometric, duplicate	2.48	%	≤ 8.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	5.02	%	≤ 10.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	1.02	%	—	NOT TESTED
Endotoxin	kinetic chromogenic LAL	5.99	EU/mg	≤ 5.0	FAIL
Sterility	not ordered on this submission	not determined	—	no growth	NOT TESTED
Appearance	visual, diffuse light, black and white background	White cake, partial shrinkage from vial wall	—	white to off-white intact cake	FAIL
Reconstitution clarity	reconstituted per submitter procedure	Clear after 90 s gentle swirling, no particulates	—	clear, no visible particulates	PASS
pH (reconstituted, 1 mg/mL)	potentiometric, two-point calibration	4.53	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 30 min gradient	9.84	min	9.84 ± 0.25 (normalised)	PASS
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	1.02	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	66,257	—	≥ 20,000	PASS
Resolution to nearest impurity	vs des-acetyl MT-II (−42 Da)	3.06	—	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, 30 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 66,257, and skew follows the reported asymmetry factor of 1.02. 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 0.04 % impurity against a 99.93 % 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	Melanotan II — main peak	9.84	4,856,908	99.93	—
2	des-acetyl MT-II (−42 Da)	9.36	1,944	0.04	-42.011
3	linear (open-lactam) precursor (+18 Da)	9.10	1,458	0.03	+18.011
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 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)	99.90	99.93	divergence -0.03 pp vs batch median
Total impurities (% area)	0.10	0.07
Largest single impurity (% area)	0.06	0.04
Water (%)	not stated	2.48
Counter-ion (%)	5.6	5.02
Peptide content (%w/w)	90.3	not determined
Endotoxin (EU/mg)	not stated	5.99
Method stated on certificate	NO	—	no 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: Supplier-supplied
Evidentiary weight: Weaker evidence. Read with the caveat below.
Chain of custody: Supplier despatch → laboratory direct (courier, cold pack, 11 d) → assay. Submitter did not handle the vial.
Assay date: 13 Sep 2024
Submitted to the index: 29 Sep 2024
Laboratory: Janoshik Analytical, Ostrava, Czechia
Method basis: 30 min gradient · high-resolution MS
Verification status: PURITY ONLY

What this report does not establish

That the compound is the compound named. No identity confirmation was ordered on this submission. A purity figure describes chromatographic homogeneity of whatever eluted; it does not name it.
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 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 5

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.

lal_assay29 Sep 2024

5.99 EU/mg is above the index screening threshold of 5.0. Two things to keep separate: the index threshold is a screening figure, and a real limit is dose-dependent. The endotoxin dose-limit calculator does that arithmetic. What this record establishes is that the burden is measurable and high relative to the rest of the dataset.

endotoxin_limit29 Sep 2024

Endotoxin burden at this level usually tracks water quality at the fill step rather than anything about the synthesis. A high-purity lot with high endotoxin is an entirely coherent result and this is one.

Contributor #M-368429 Sep 2024

5.99 EU/mg from an older lot. Endotoxins are heat-stable and drift is rare. If this matches fresh-lot median from the same supplier, the number is stable.

pyroglutamate29 Sep 2024

Purity 99.93 % and endotoxin 5.99 EU/mg are unrelated — purity measures synthesis quality, endotoxin measures fill-step water quality. The combination here is coherent and expected together.

salt_exchange29 Sep 2024

Endotoxin assay but no bacterial viability or total count. The two are independent: dead endotoxin-bearing bacteria contribute to the burden, living ones that produce endotoxins do not.

Section 7

Related records

Same batch — lot QSC-2402-G9476 n=1

This is the only report on this lot. One report is not a batch characterisation.

Batch rollup and reproducibility assessment →

Cross-sections

Other recent Melanotan II records in the index.
Report	Supplier	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-042648	GGPeps	GGPE-2603-P8735	Janoshik	2026-Q3	99.10	6.97	—	Supplier-supplied	4	MARGINAL
AX-2026-042479	SWB	SWB-2603-A5707	Janoshik	2026-Q3	99.16	3.67	94.5	Supplier-supplied	1	MARGINAL
AX-2026-042481	SWB	SWB-2603-A5707	Medutest	2026-Q3	98.95	3.37	90.8	Supplier-supplied	1	MARGINAL
AX-2026-042650	GGPeps	GGPE-2603-P8735	Medutest	2026-Q3	99.86	6.49	—	Supplier-supplied	3	MARGINAL
AX-2026-042483	SWB	SWB-2603-A5707	Janoshik	2026-Q3	99.38	3.73	107.2	Supplier-supplied	1	MARGINAL
AX-2026-042651	GGPeps	GGPE-2603-P8735	PeptideMeter	2026-Q3	99.53	7.04	90.7	Supplier-supplied	4	MARGINAL
AX-2026-042478	SWB	SWB-2603-A5707	VendorInvestigate	2026-Q3	98.73	4.34	—	Buyer-sourced	1	MARGINAL
AX-2026-042482	SWB	SWB-2603-A5707	Janoshik	2026-Q3	99.22	4.66	—	Supplier-supplied	1	MARGINAL

Other recent QSC records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041683	CJC-1295 (no DAC)	QSC-2606-V8637	Janoshik	2026-Q3	99.93	3.63	97.1	Supplier-supplied	1	FAIL
AX-2026-041727	CJC-1295 with DAC	QSC-2602-E9474	Janoshik	2026-Q3	98.88	6.62	105.3	Supplier-supplied	1	MARGINAL
AX-2026-041728	CJC-1295 with DAC	QSC-2602-E9474	VendorInvestigate	2026-Q3	98.42	7.04	—	Buyer-sourced	1	MARGINAL
AX-2026-041734	CJC-1295 with DAC	QSC-2602-E9474	Medutest	2026-Q3	99.43	7.17	105.5	Supplier-supplied	2	FAIL
AX-2026-041652	Liraglutide	QSC-2605-W8602	Nordanalyt	2026-Q3	99.33	6.55	—	Supplier-supplied	0	PASS
AX-2026-041730	CJC-1295 with DAC	QSC-2602-E9474	PeptideMeter	2026-Q3	98.79	6.93	95.4	Supplier-supplied	1	MARGINAL
AX-2026-041686	CJC-1295 (no DAC)	QSC-2606-V8637	Janoshik	2026-Q3	99.93	4.04	—	Supplier-supplied	0	PASS
AX-2026-041653	Liraglutide	QSC-2605-W8602	VendorInvestigate	2026-Q3	98.82	5.95	—	Buyer-sourced	0	PASS