AX-2024-004618 · PT-141 (Bremelanotide) · TFC lot TFC-2310-J1196

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, 25 min gradient, 214 nm	99.71	% area	≥ 98.5	PASS
Total impurities	RP-HPLC, sum of reported peaks	0.29	% area	≤ 1.5	PASS
Largest single impurity	RP-HPLC — linear precursor (+18 Da)	0.18	% area	≤ 1.00	PASS
Identity — theoretical monoisotopic mass	calculated from molecular formula	1024.5242	Da	—	NOT TESTED
Identity — observed monoisotopic mass	LC-MS, unit resolution (single quadrupole)	1024.5211	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	-3.0	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	8.01	%	≤ 8.0	FAIL
Counter-ion (acetate)	anion-exchange ion chromatography	4.81	%	≤ 10.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.19	%	—	NOT TESTED
Endotoxin	kinetic chromogenic LAL	2.86	EU/mg	≤ 5.0	PASS
Sterility	membrane filtration, USP <71>, 14 d	No growth at 14 d	—	no growth	PASS
Appearance	visual, diffuse light, black and white background	White powder, no defined cake (melt-back)	—	white to off-white intact cake	FAIL
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	5.81	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 25 min gradient	8.17	min	8.06 ± 0.25 (normalised)	PASS
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	1.05	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	69,226	—	≥ 20,000	PASS
Resolution to nearest impurity	vs melanotan II (C-terminal amide, −1 Da)	2.09	—	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 69,226, and skew follows the reported asymmetry factor of 1.05. 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 0.18 % impurity against a 99.71 % 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	8.17	4,846,215	99.71	—
2	linear precursor (+18 Da)	7.59	8,749	0.18	+18.011
3	des-acetyl (−42 Da)	7.79	3,402	0.07	-42.011
4	melanotan II (C-terminal amide, −1 Da)	8.44	972	0.02	-0.984
5	oxidised Trp (+16 Da)	7.89	972	0.02	+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 1024.5242 Da, computed from C50H68N14O10. 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 1024.5211 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+	342.5153	342.5143	-0.0010	8.0
2+	513.2694	513.2678	-0.0016	51.2
1+	1025.5315	1025.5284	-0.0031	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)	99.90	99.71	divergence -0.03 pp vs batch median
Total impurities (% area)	0.10	0.29
Largest single impurity (% area)	0.04	0.18
Water (%)	6.8	8.01
Counter-ion (%)	5.2	4.81
Peptide content (%w/w)	87.4	not determined
Endotoxin (EU/mg)	not stated	2.86
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: Laboratory-retained
Evidentiary weight: Provenance documented, selection uncontrolled.
Chain of custody: Laboratory retained sample (−20 °C, 27 d since original receipt) → re-assay.
Assay date: 11 Jan 2024
Submitted to the index: 13 Jan 2024
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 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.

valley_drop13 Jan 2024

Largest single impurity is linear precursor (+18 Da) at 0.18 % area, and it is the only named peak above 0.1 %. The integration is unambiguous and 99.71 % can be taken at face value.

ms_confirm13 Jan 2024

Two instruments or it is not confirmed, and this record is one instrument. It is a good one instrument, and the index records it as confirmed rather than corroborated for that reason.

survodutide_mixup13 Jan 2024

Where two compounds elute within a third of a minute, a mass at this accuracy is what separates them. Retention alone would not have.

Section 7

Related records

Same batch — lot TFC-2310-J1196 n=11

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Result
AX-2024-004609	TFC-2310-J1196	Medutest	2024-Q1	99.70	7.95	—	Laboratory-retained	PASS
AX-2024-004610	TFC-2310-J1196	Janoshik	2024-Q1	99.74	7.37	96.4	Buyer-sourced	PASS
AX-2024-004611	TFC-2310-J1196	Janoshik	2024-Q1	99.93	7.86	90.5	Buyer-sourced	PASS
AX-2024-004612	TFC-2310-J1196	Janoshik	2024-Q1	99.93	7.65	103.0	Buyer-sourced	PASS
AX-2024-004613	TFC-2310-J1196	Janoshik	2024-Q1	99.93	8.09	107.1	Buyer-sourced	FAIL
AX-2024-004614	TFC-2310-J1196	Janoshik	2024-Q1	99.93	8.49	99.7	Buyer-sourced	FAIL
AX-2024-004615	TFC-2310-J1196	Janoshik	2024-Q1	99.84	7.71	—	Buyer-sourced	PASS
AX-2024-004616	TFC-2310-J1196	Janoshik	2024-Q1	99.93	7.79	—	Buyer-sourced	PASS
AX-2024-004617	TFC-2310-J1196	Nordanalyt	2024-Q1	99.93	8.62	100.9	Buyer-sourced	FAIL
AX-2024-004619	TFC-2310-J1196	PeptideMeter	2024-Q1	99.82	7.57	—	Buyer-sourced	PASS

Batch rollup and reproducibility assessment →

Cross-sections

All PT-141 (Bremelanotide) records n=152
All TFC records n=417
All Medutest records n=934
All 2024-Q1 records n=161
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 TFC records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-042265	Humanin (HNG)	TFC-2605-U1300	PeptideMeter	2026-Q3	99.52	6.31	—	Buyer-sourced	0	PASS
AX-2026-042222	SS-31 (Elamipretide)	TFC-2607-R9099	VendorInvestigate	2026-Q3	99.46	5.41	102.6	Buyer-sourced	0	PASS
AX-2026-042236	Humanin (HNG)	TFC-2608-S9940	Nordanalyt	2026-Q3	98.64	1.80	—	Buyer-sourced	0	PASS
AX-2026-042282	Retatrutide	TFC-2608-J1156	Janoshik	2026-Q3	98.54	4.27	—	Buyer-sourced	0	PASS
AX-2026-042226	SS-31 (Elamipretide)	TFC-2607-R9099	Janoshik	2026-Q3	99.62	5.47	—	Buyer-sourced	0	PASS
AX-2026-042217	Semaglutide	TFC-2604-X9037	PeptideMeter	2026-Q3	98.95	4.61	96.9	Buyer-sourced	0	PASS
AX-2026-042339	Sermorelin	TFC-2605-Y2176	Kestrel	2026-Q3	99.93	4.14	—	Supplier-supplied	1	FAIL
AX-2026-042214	Semaglutide	TFC-2604-X9037	Kestrel	2026-Q3	99.87	4.66	103.1	Laboratory-retained	0	PASS