AX-2026-041856 · PT-141 (Bremelanotide) · GSP lot GSP-2512-N3921

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	99.66	% area	≥ 98.5	PASS
Total impurities	RP-HPLC, sum of reported peaks	0.34	% area	≤ 1.5	PASS
Largest single impurity	RP-HPLC — melanotan II (C-terminal amide, −1 Da)	0.14	% area	≤ 1.00	PASS
Identity	not ordered on this submission	not determined	—	required for VERIFIED status	NOT TESTED
Total peptide content	by difference from the gravimetric mass balance	88.77	%w/w	—	NOT TESTED
Target-compound content	total peptide content × purity	88.47	%w/w	—	NOT TESTED
Gross fill (as weighed)	five-place balance, under nitrogen	10.79	mg	10 mg declared	NOT TESTED
Recovered target peptide	gross fill × target content	9.546	mg	10 mg claim	NOT TESTED
Recovery against label claim	recovered ÷ claim	95.5	%	90.0 – 110.0	PASS
Water content	Karl Fischer, coulometric, duplicate	5.25	%	≤ 8.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	5.62	%	≤ 10.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.36	%	—	NOT TESTED
Endotoxin	kinetic chromogenic LAL	2.58	EU/mg	≤ 5.0	PASS
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	4.70	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 30 min gradient	9.46	min	9.52 ± 0.25 (normalised)	PASS
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	1.01	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	76,445	—	≥ 20,000	PASS
Resolution to nearest impurity	vs melanotan II (C-terminal amide, −1 Da)	2.28	—	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 76,445, and skew follows the reported asymmetry factor of 1.01. 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 0.14 % impurity against a 99.66 % 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	PT-141 (Bremelanotide) — main peak	9.46	4,843,785	99.66	—
2	melanotan II (C-terminal amide, −1 Da)	9.78	6,804	0.14	-0.984
3	linear precursor (+18 Da)	8.76	4,860	0.10	+18.011
4	oxidised Trp (+16 Da)	9.12	2,916	0.06	+15.995
5	des-acetyl (−42 Da)	9.00	1,944	0.04	-42.011
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.

Component	Determination	%w/w of cake
Water	Karl Fischer	5.25
Counter-ion (acetate)	ion chromatography	5.62
Residual solvent + inorganic residue	estimated	0.36
Total peptide content	by difference	88.77
Total		100.00 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.

Figure	Supplier COA	This report	Index note
Purity (% area)	99.24	99.66	divergence -0.41 pp vs batch median
Total impurities (% area)	0.76	0.34
Largest single impurity (% area)	0.46	0.14
Water (%)	3.9	5.25
Counter-ion (%)	not stated	5.62
Peptide content (%w/w)	91.3	88.77
Endotoxin (EU/mg)	1.98	2.58
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, 3 d) → assay. Submitter did not handle the vial.
Assay date: 22 Apr 2026
Submitted to the index: 28 Apr 2026
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.
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 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.

power_analysis28 Apr 2026

To detect a half-point difference between provenance classes on one supplier you need more paired lots than most suppliers have. The index-wide figure is well determined; the per-supplier ones mostly are not.

sole_source28 Apr 2026

Where this is the only record on a compound, the index says so on the compound page rather than reporting a median over one observation. Provenance is the second caveat there, not the first.

aaa_hydrolysis28 Apr 2026

Content by hydrolysis assumes complete recovery of every residue. Where it disagrees with the balance by a percent or two, the hydrolysis is the more likely culprit.

Section 7

Related records

Same batch — lot GSP-2512-N3921 n=8

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041850	GSP-2512-N3921	PeptideMeter	2026-Q2	99.86	5.34	91.6	Buyer-sourced	0	PASS
AX-2026-041851	GSP-2512-N3921	Nordanalyt	2026-Q2	99.70	5.26	—	Buyer-sourced	0	PASS
AX-2026-041852	GSP-2512-N3921	Nordanalyt	2026-Q2	99.62	5.44	90.6	Buyer-sourced	0	PASS
AX-2026-041853	GSP-2512-N3921	Janoshik	2026-Q2	99.70	5.43	93.7	Supplier-supplied	0	PASS
AX-2026-041854	GSP-2512-N3921	VendorInvestigate	2026-Q2	99.21	4.84	—	Buyer-sourced	0	PASS
AX-2026-041855	GSP-2512-N3921	Janoshik	2026-Q2	99.29	5.54	89.8	Buyer-sourced	1	MARGINAL
AX-2026-041857	GSP-2512-N3921	Janoshik	2026-Q2	99.64	5.00	98.7	Buyer-sourced	0	PASS

Batch rollup and reproducibility assessment →

Cross-sections

All PT-141 (Bremelanotide) records n=152
All GSP records n=180
All Janoshik records n=2989
All 2026-Q2 records n=1126
PT-141 (Bremelanotide) by supplier
PT-141 (Bremelanotide) impurity profile

Other recent PT-141 (Bremelanotide) records in the index.
Report	Supplier	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041471	QYB	QYB-2607-L4875	Janoshik	2026-Q3	99.72	3.75	101.7	Buyer-sourced	0	PASS
AX-2026-041473	QYB	QYB-2607-L4875	PeptideMeter	2026-Q3	99.58	3.74	94.4	Buyer-sourced	0	PASS
AX-2026-041472	QYB	QYB-2607-L4875	PeptideMeter	2026-Q3	99.93	3.94	—	Buyer-sourced	0	PASS
AX-2026-041474	QYB	QYB-2607-L4875	VendorInvestigate	2026-Q3	99.16	3.78	95.6	Buyer-sourced	0	PASS
AX-2026-041470	QYB	QYB-2607-L4875	Janoshik	2026-Q3	99.77	4.10	—	Buyer-sourced	0	PASS
AX-2026-042139	JEEP	JEEP-2601-K8195	VendorInvestigate	2026-Q2	98.32	4.29	99.4	Buyer-sourced	1	FAIL
AX-2026-041964	AMB	AMB-2601-M5602	Janoshik	2026-Q2	99.93	3.20	—	Buyer-sourced	0	PASS
AX-2026-041664	FGP	FGP-2602-Y8741	Janoshik	2026-Q2	99.90	4.48	106.5	Buyer-sourced	0	PASS

Other recent GSP records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041831	Survodutide	GSP-2603-E3156	Kestrel	2026-Q3	99.91	5.50	93.2	Buyer-sourced	0	PASS
AX-2026-041836	Survodutide	GSP-2603-E3156	Janoshik	2026-Q3	98.65	5.34	90.3	Buyer-sourced	0	PASS
AX-2026-041837	Survodutide	GSP-2603-E3156	Janoshik	2026-Q3	98.33	5.37	—	Buyer-sourced	0	PASS
AX-2026-041833	Survodutide	GSP-2603-E3156	Janoshik	2026-Q3	98.08	4.91	99.3	Buyer-sourced	0	PASS
AX-2026-041832	Survodutide	GSP-2603-E3156	VendorInvestigate	2026-Q3	98.01	5.14	99.5	Buyer-sourced	0	PASS
AX-2026-041835	Survodutide	GSP-2603-E3156	Nordanalyt	2026-Q3	98.34	5.74	89.0	Buyer-sourced	1	MARGINAL
AX-2026-041834	Survodutide	GSP-2603-E3156	VendorInvestigate	2026-Q3	97.92	5.95	—	Buyer-sourced	0	PASS
AX-2026-041838	Survodutide	GSP-2603-E3156	PeptideMeter	2026-Q3	98.30	5.01	102.4	Buyer-sourced	0	PASS