AssayIndex

AX-2026-042116

PT-141 (Bremelanotide) · 10 mg declared · Tianjin Finder Chemical Co., Ltd. · lot TFC-2512-M8211

MARGINALIDENTITY CONSISTENT
Report ID
AX-2026-042116
Compound
PT-141 (Bremelanotide)
Compound class
Melanocortin-receptor peptides
Supplier
TFC — Tianjin Finder Chemical Co., Ltd.
Batch / lot
TFC-2512-M8211
Declared label claim
10mg
Laboratory
Medutest
Assay date
19 May 2026
Submitted
31 May 2026
Quarter
2026-Q2
Submitter
a.palacios
Sample provenance
Laboratory-retained
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.

ParameterMethodResultUnitIndex spec
PurityRP-HPLC, 25 min gradient, 214 nm99.02% area≥ 98.5PASS
Total impuritiesRP-HPLC, sum of reported peaks0.98% area≤ 1.5PASS
Largest single impurityRP-HPLC — melanotan II (C-terminal amide, −1 Da)0.37% area≤ 1.00PASS
Identity — theoretical monoisotopic masscalculated from molecular formula1024.5242DaNOT TESTED
Identity — observed monoisotopic massLC-MS, unit resolution (single quadrupole)1024.5205DaNOT TESTED
Mass accuracyobserved vs theoretical-3.6ppm± 15PASS
Total peptide contentby difference from the gravimetric mass balance88.02%w/wNOT TESTED
Target-compound contenttotal peptide content × purity87.16%w/wNOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen11.88mg10 mg declaredNOT TESTED
Recovered target peptidegross fill × target content10.355mg10 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim103.6%90.0 – 110.0PASS
Water contentKarl Fischer, coulometric, duplicate7.26%≤ 8.0PASS
Counter-ion (acetate)anion-exchange ion chromatography4.18%≤ 10.0PASS
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.54%NOT TESTED
Endotoxinkinetic chromogenic LAL0.46EU/mg≤ 5.0PASS
Sterilitynot ordered on this submissionnot determinedno growthNOT TESTED
Appearancevisual, diffuse light, black and white backgroundWhite cake, partially collapsedwhite to off-white intact cakeFAIL
Reconstitution clarityreconstituted per submitter procedureClear after 90 s gentle swirling, no particulatesclear, no visible particulatesPASS
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration5.732.5 – 8.0PASS
Retention time (observed)RP-HPLC, 25 min gradient7.89min8.06 ± 0.25 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.460.990.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²69,626≥ 20,000PASS
Resolution to nearest impurityvs melanotan II (C-terminal amide, −1 Da)2.18no index criterionREPORTED
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.

0385377051155815410 PT-141 (Bremelanotide)7.89 min · 99.02 % 7.61 same trace · ×100 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 0481216202428 Retention time (min) Response (mAU)
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 69,626, and skew follows the reported asymmetry factor of 0.99. 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 0.37 % impurity against a 99.02 % main peak is a line two pixels tall; the main peak runs off-scale there by design.
#PeakRTArea (µV·s)% areaΔ mass (Da)
1PT-141 (Bremelanotide) — main peak7.894,812,67999.02
2melanotan II (C-terminal amide, −1 Da)8.1617,9830.37-0.984
3oxidised Trp (+16 Da)7.6117,0110.35+15.995
4des-acetyl (−42 Da)7.516,3180.13-42.011
5linear precursor (+18 Da)7.316,3180.13+18.011
Closure check — purity + Σ impurities 100.00CLOSES

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.

025507510025040055070085010001150 [M+1H]1+1025.53[M+2H]2+513.27 m/z Relative abundance (%)
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 1024.5205 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.
ChargeTheoretical m/zObserved m/zΔ m/zRel. abundance (%)
3+342.5153342.5141-0.00128.1
2+513.2694513.2675-0.001952.6
1+1025.53151025.5278-0.0037100.0
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.

ComponentDetermination%w/w of cake
WaterKarl Fischer7.26
Counter-ion (acetate)ion chromatography4.18
Residual solvent + inorganic residueestimated0.54
Total peptide contentby difference88.02
Total100.00 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.

FigureSupplier COAThis reportIndex note
Purity (% area)99.5199.02divergence +0.38 pp vs batch median
Total impurities (% area)not stated0.98
Largest single impurity (% area)not stated0.37
Water (%)6.07.26
Counter-ion (%)not stated4.18
Peptide content (%w/w)not stated88.02
Endotoxin (EU/mg)0.260.46
Method stated on certificateYEScolumn, 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, 8 d since original receipt) → re-assay.
Assay date
19 May 2026
Submitted to the index
31 May 2026
Laboratory
Medutest, Ljubljana, Slovenia
Method basis
25 min gradient · unit-resolution MS
Verification status
IDENTITY CONSISTENT
Section 6

Annotations

No annotations on this record. Annotations are short signed technical comments from index contributors; see how to contribute.

Section 7

Related records

Same batch — lot TFC-2512-M8211 n=9

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042113TFC-2512-M8211Janoshik2026-Q299.137.1098.4Supplier-supplied1MARGINAL
AX-2026-042114TFC-2512-M8211PeptideMeter2026-Q298.737.99Supplier-supplied1MARGINAL
AX-2026-042115TFC-2512-M8211Janoshik2026-Q299.197.08103.0Supplier-supplied1MARGINAL
AX-2026-042117TFC-2512-M8211Nordanalyt2026-Q298.657.3393.7Laboratory-retained1MARGINAL
AX-2026-042118TFC-2512-M8211Janoshik2026-Q299.137.21101.1Supplier-supplied1MARGINAL
AX-2026-042119TFC-2512-M8211Janoshik2026-Q299.207.0989.1Supplier-supplied2MARGINAL
AX-2026-042120TFC-2512-M8211Janoshik2026-Q298.716.46Laboratory-retained1MARGINAL
AX-2026-042121TFC-2512-M8211PeptideMeter2026-Q299.397.14Supplier-supplied1MARGINAL
Other recent PT-141 (Bremelanotide) records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041488QYBQYB-2607-L5615Janoshik2026-Q399.933.79Supplier-supplied0PASS
AX-2026-041483QYBQYB-2607-L5615Janoshik2026-Q399.933.87Supplier-supplied0PASS
AX-2026-041482QYBQYB-2607-L5615PeptideMeter2026-Q399.413.97Supplier-supplied0PASS
AX-2026-041489QYBQYB-2607-L5615PeptideMeter2026-Q399.404.3990.1Supplier-supplied0PASS
AX-2026-041480QYBQYB-2607-L5615Medutest2026-Q399.934.32100.5Supplier-supplied0PASS
AX-2026-041481QYBQYB-2607-L5615Kestrel2026-Q399.933.63100.5Supplier-supplied0PASS
AX-2026-041487QYBQYB-2607-L5615Nordanalyt2026-Q399.434.03Supplier-supplied0PASS
AX-2026-041486QYBQYB-2607-L5615Nordanalyt2026-Q399.623.82104.9Supplier-supplied0PASS
Other recent TFC records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041932SemaglutideTFC-2604-X4301Janoshik2026-Q398.884.31Supplier-supplied0PASS
AX-2026-042067SS-31 (Elamipretide)TFC-2604-Y7472Kestrel2026-Q398.664.44Supplier-supplied1MARGINAL
AX-2026-042057SermorelinTFC-2605-Y6440Janoshik2026-Q398.683.9498.3Supplier-supplied0PASS
AX-2026-041936SemaglutideTFC-2604-X4301PeptideMeter2026-Q398.624.30Buyer-sourced1MARGINAL
AX-2026-041973Humanin (HNG)TFC-2605-U5564Janoshik2026-Q399.627.03Supplier-supplied2FAIL
AX-2026-041980Humanin (HNG)TFC-2605-U5564Janoshik2026-Q399.907.0188.6Supplier-supplied2MARGINAL
AX-2026-041961TirzepatideTFC-2605-G5134Medutest2026-Q398.257.11Supplier-supplied2MARGINAL
AX-2026-042068SS-31 (Elamipretide)TFC-2604-Y7472Medutest2026-Q398.713.6392.9Supplier-supplied2MARGINAL