AX-2026-042164

Melanotan II · 10 mg declared · Guangzhou JEEP Biotechnology Co., Ltd. · lot JEEP-2604-R9103

MARGINALIDENTITY CONSISTENT

Report ID: AX-2026-042164
Compound: Melanotan II
Compound class: Melanocortin-receptor peptides
Supplier: JEEP — Guangzhou JEEP Biotechnology Co., Ltd.
Batch / lot: JEEP-2604-R9103
Declared label claim: 10mg
Laboratory: Janoshik Analytical
Assay date: 19 Jun 2026
Submitted: 10 Jul 2026
Quarter: 2026-Q2
Submitter: l.erdogan
Sample provenance: Buyer-sourced

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	99.54	% area	≥ 98.5	PASS
Total impurities	RP-HPLC, sum of reported peaks	0.46	% area	≤ 1.5	PASS
Largest single impurity	RP-HPLC — linear (open-lactam) precursor (+18 Da)	0.30	% area	≤ 1.00	PASS
Identity — theoretical monoisotopic mass	calculated from molecular formula	1023.5402	Da	—	NOT TESTED
Identity — observed monoisotopic mass	LC-MS, high resolution (ESI-TOF/QTOF)	1023.5381	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	-2.1	ppm	± 15	PASS
Peptide content	not ordered on this submission	not determined	—	required to check label claim	NOT TESTED
Water content	Karl Fischer, coulometric, duplicate	5.23	%	≤ 8.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	5.76	%	≤ 10.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.18	%	—	NOT TESTED
Endotoxin	not ordered on this submission	not determined	—	≤ 5.0	NOT TESTED
Sterility	membrane filtration, USP <71>, 14 d	No growth at 14 d	—	no growth	PASS
Appearance	visual, diffuse light, black and white background	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	5.18	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 30 min gradient	10.13	min	9.84 ± 0.25 (normalised)	FAIL
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	1.16	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	41,311	—	≥ 20,000	PASS
Resolution to nearest impurity	vs [L-Phe7]-diastereomer	0.78	—	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 41,311, and skew follows the reported asymmetry factor of 1.16. 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 0.30 % impurity against a 99.54 % 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	10.13	4,837,953	99.54	—
2	linear (open-lactam) precursor (+18 Da)	9.39	14,581	0.30	+18.011
3	des-acetyl MT-II (−42 Da)	9.65	3,402	0.07	-42.011
4	[L-Phe7]-diastereomer	9.97	2,430	0.05	0.000
5	oxidised Trp (+16 Da)	9.77	1,944	0.04	+15.995
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 1023.5402 Da, computed from C50H69N15O9. All ppm figures on this site are against monoisotopic values — see why that matters.

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 1023.5381 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 (%)
3+	342.1873	342.1866	-0.0007	8.2
2+	512.7774	512.7763	-0.0011	51.7
1+	1024.5475	1024.5454	-0.0021	100.0

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.

Figure	Supplier COA	This report	Index note
Purity (% area)	99.14	99.54	divergence -0.36 pp vs batch median
Total impurities (% area)	0.86	0.46
Largest single impurity (% area)	not stated	0.30
Water (%)	not stated	5.23
Counter-ion (%)	9.1	5.76
Peptide content (%w/w)	86.8	not determined
Endotoxin (EU/mg)	not stated	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 (2–8 °C, 34 d) → laboratory (courier, ambient, 7 d) → assay.
Assay date: 19 Jun 2026
Submitted to the index: 10 Jul 2026
Laboratory: Janoshik Analytical, Ostrava, Czechia
Method basis: 30 min gradient · high-resolution MS
Verification status: IDENTITY CONSISTENT

What this report does not establish

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 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.

nmr_qnmr10 Jul 2026

Mass at -2.1 ppm establishes identity but not content. Absolute content needs a standard or an orthogonal quantitative method, and neither is a mass spectrometer.

shipping_temp10 Jul 2026

The custody block above records the shipping conditions this vial actually experienced, which is the condition an ordinary buyer's vial experiences too. That representativeness is the point.

coa_reader10 Jul 2026

The certificate that arrives with a retail order is the certificate an ordinary buyer gets. Assessing it is assessing the real documentation practice rather than the sample-request one.

dedupe_logic10 Jul 2026

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 JEEP-2604-R9103 n=13

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Result
AX-2026-042165	JEEP-2604-R9103	Janoshik	2026-Q2	99.76	5.24	—	Buyer-sourced	PASS
AX-2026-042166	JEEP-2604-R9103	Janoshik	2026-Q2	99.40	4.75	—	Buyer-sourced	PASS
AX-2026-042167	JEEP-2604-R9103	Nordanalyt	2026-Q2	99.90	5.71	—	Laboratory-retained	PASS
AX-2026-042168	JEEP-2604-R9103	Nordanalyt	2026-Q2	99.40	5.71	—	Buyer-sourced	PASS
AX-2026-042169	JEEP-2604-R9103	Janoshik	2026-Q2	99.43	5.22	—	Buyer-sourced	PASS
AX-2026-042170	JEEP-2604-R9103	Medutest	2026-Q2	99.92	5.07	—	Buyer-sourced	PASS
AX-2026-042171	JEEP-2604-R9103	Kestrel	2026-Q2	99.59	5.11	—	Buyer-sourced	PASS
AX-2026-042172	JEEP-2604-R9103	VendorInvestigate	2026-Q2	99.72	5.39	105.7	Buyer-sourced	PASS
AX-2026-042173	JEEP-2604-R9103	Janoshik	2026-Q2	99.38	5.31	—	Buyer-sourced	PASS
AX-2026-042174	JEEP-2604-R9103	PeptideMeter	2026-Q2	99.22	5.42	—	Buyer-sourced	PASS
AX-2026-042175	JEEP-2604-R9103	Janoshik	2026-Q2	99.19	5.45	—	Buyer-sourced	PASS
AX-2026-042176	JEEP-2604-R9103	Janoshik	2026-Q2	99.50	4.88	105.3	Buyer-sourced	PASS

Batch rollup and reproducibility assessment →

Cross-sections

Other recent Melanotan II records in the index.
Report	Supplier	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Result
AX-2026-042757	GGPeps	GGPE-2603-P1474	Janoshik	2026-Q3	99.54	6.78	92.0	Buyer-sourced	PASS
AX-2026-042756	GGPeps	GGPE-2603-P1474	Nordanalyt	2026-Q3	99.17	7.04	—	Buyer-sourced	PASS
AX-2026-042755	GGPeps	GGPE-2603-P1474	Nordanalyt	2026-Q3	99.25	6.58	90.4	Buyer-sourced	PASS
AX-2026-042760	GGPeps	GGPE-2603-P1474	Medutest	2026-Q3	99.43	7.02	—	Buyer-sourced	PASS
AX-2026-042758	GGPeps	GGPE-2603-P1474	PeptideMeter	2026-Q3	99.23	6.96	—	Buyer-sourced	PASS
AX-2026-042759	GGPeps	GGPE-2603-P1474	Janoshik	2026-Q3	99.15	6.71	105.1	Buyer-sourced	PASS
AX-2026-042168	JEEP	JEEP-2604-R9103	Nordanalyt	2026-Q2	99.40	5.71	—	Buyer-sourced	PASS
AX-2026-042171	JEEP	JEEP-2604-R9103	Kestrel	2026-Q2	99.59	5.11	—	Buyer-sourced	PASS

Other recent JEEP records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-042177	Hexarelin	JEEP-2608-Y9547	Janoshik	2026-Q3	99.90	3.42	—	Buyer-sourced	0	PASS
AX-2026-042162	Semaglutide	JEEP-2607-X9091	Janoshik	2026-Q3	98.98	3.46	—	Laboratory-retained	1	MARGINAL
AX-2026-042127	TB-500	JEEP-2602-V8614	Medutest	2026-Q3	99.68	3.55	—	Buyer-sourced	1	FAIL
AX-2026-042123	TB-500	JEEP-2602-V8614	PeptideMeter	2026-Q3	99.93	3.80	—	Buyer-sourced	0	PASS
AX-2026-042124	TB-500	JEEP-2602-V8614	PeptideMeter	2026-Q3	99.91	3.37	104.9	Buyer-sourced	0	PASS
AX-2026-042178	Hexarelin	JEEP-2608-Y9547	VendorInvestigate	2026-Q3	99.68	4.03	—	Buyer-sourced	0	PASS
AX-2026-042163	Semaglutide	JEEP-2607-X9091	Nordanalyt	2026-Q3	99.46	4.52	—	Buyer-sourced	1	MARGINAL
AX-2026-042122	TB-500	JEEP-2602-V8614	PeptideMeter	2026-Q3	99.60	3.58	97.0	Buyer-sourced	0	PASS