AssayIndex

AX-2025-020979

PT-141 (Bremelanotide) · 10 mg declared · WuXi TIDES (WuXi AppTec Testing Division) · lot WXT-2507-R4042

PASSPURITY ONLY
Report ID
AX-2025-020979
Compound
PT-141 (Bremelanotide)
Compound class
Melanocortin-receptor peptides
Supplier
WXT — WuXi TIDES (WuXi AppTec Testing Division)
Batch / lot
WXT-2507-R4042
Declared label claim
10mg
Laboratory
Janoshik Analytical
Assay date
31 Jul 2025
Submitted
14 Aug 2025
Quarter
2025-Q3
Submitter
b.kaufmann
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.

ParameterMethodResultUnitIndex spec
PurityRP-HPLC, 30 min gradient, 214 nm99.11% area≥ 98.5PASS
Total impuritiesRP-HPLC, sum of reported peaks0.89% area≤ 1.5PASS
Largest single impurityRP-HPLC — linear precursor (+18 Da)0.42% area≤ 1.00PASS
Identitynot ordered on this submissionnot determinedrequired for VERIFIED statusNOT TESTED
Total peptide contentby difference from the gravimetric mass balance88.87%w/wNOT TESTED
Target-compound contenttotal peptide content × purity88.08%w/wNOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen10.58mg10 mg declaredNOT TESTED
Recovered target peptidegross fill × target content9.319mg10 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim93.2%90.0 – 110.0PASS
Water contentKarl Fischer, coulometric, duplicate4.85%≤ 8.0PASS
Counter-ion (acetate)anion-exchange ion chromatography5.39%≤ 10.0PASS
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.89%NOT TESTED
Endotoxinnot ordered on this submissionnot determined≤ 5.0NOT TESTED
Sterilitynot ordered on this submissionnot determinedno growthNOT TESTED
Appearancevisual, diffuse light, black and white backgroundWhite lyophilised cake, intactwhite to off-white intact cakePASS
Reconstitution clarityreconstituted per submitter procedureClear with a single visible fibreclear, no visible particulatesFAIL
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration5.172.5 – 8.0PASS
Retention time (observed)RP-HPLC, 30 min gradient9.59min9.52 ± 0.25 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.461.150.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²58,829≥ 20,000PASS
Resolution to nearest impurityvs melanotan II (C-terminal amide, −1 Da)1.97no 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.

026995398809810797 PT-141 (Bremelanotide)9.59 min · 99.11 % 8.89 same trace · ×100 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 05101520253035 Retention time (min) Response (mAU)
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 58,829, and skew follows the reported asymmetry factor of 1.15. 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 0.42 % impurity against a 99.11 % 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 peak9.594,817,05399.11
2linear precursor (+18 Da)8.8920,4130.42+18.011
3melanotan II (C-terminal amide, −1 Da)9.9112,1510.25-0.984
4des-acetyl (−42 Da)9.135,8320.12-42.011
5oxidised Trp (+16 Da)9.254,8600.10+15.995
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 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 Fischer4.85
Counter-ion (acetate)ion chromatography5.39
Residual solvent + inorganic residueestimated0.89
Total peptide contentby difference88.87
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)99.0599.11divergence +0.01 pp vs batch median
Total impurities (% area)0.950.89
Largest single impurity (% area)0.580.42
Water (%)3.94.85
Counter-ion (%)not stated5.39
Peptide content (%w/w)91.388.87
Endotoxin (EU/mg)0.75not determined
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
Buyer-sourced
Evidentiary weight
Strongest available evidence in this index.
Chain of custody
Retail purchase → submitter (−20 °C, 20 d) → laboratory (courier, dry ice, 7 d) → assay.
Assay date
31 Jul 2025
Submitted to the index
14 Aug 2025
Laboratory
Janoshik Analytical, Ostrava, Czechia
Method basis
30 min gradient · high-resolution MS
Verification status
PURITY ONLY
Section 6

Annotations 1

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.

label_claim
A retail vial is also a test of the label. Declared claim 10 mg against what the gravimetry recovers is a question only a purchased vial can answer honestly.
Section 7

Related records

Same batch — lot WXT-2507-R4042 n=12

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2025-020972WXT-2507-R4042PeptideMeter2025-Q399.045.29Buyer-sourced1MARGINAL
AX-2025-020973WXT-2507-R4042Kestrel2025-Q399.754.62Buyer-sourced0PASS
AX-2025-020974WXT-2507-R4042VendorInvestigate2025-Q399.384.71Buyer-sourced0PASS
AX-2025-020975WXT-2507-R4042Janoshik2025-Q398.884.76Buyer-sourced0PASS
AX-2025-020976WXT-2507-R4042Medutest2025-Q399.004.50101.5Buyer-sourced0PASS
AX-2025-020977WXT-2507-R4042PeptideMeter2025-Q398.984.6594.0Buyer-sourced0PASS
AX-2025-020978WXT-2507-R4042Medutest2025-Q398.654.38Buyer-sourced0PASS
AX-2025-020980WXT-2507-R4042PeptideMeter2025-Q399.264.6095.9Buyer-sourced0PASS
AX-2025-020981WXT-2507-R4042Nordanalyt2025-Q399.034.87105.2Buyer-sourced0PASS
AX-2025-020982WXT-2507-R4042Janoshik2025-Q399.324.5799.4Buyer-sourced1MARGINAL
AX-2025-020983WXT-2507-R4042Janoshik2025-Q398.975.11Laboratory-retained0PASS
Other recent PT-141 (Bremelanotide) records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041471QYBQYB-2607-L4875Janoshik2026-Q399.723.75101.7Buyer-sourced0PASS
AX-2026-041473QYBQYB-2607-L4875PeptideMeter2026-Q399.583.7494.4Buyer-sourced0PASS
AX-2026-041472QYBQYB-2607-L4875PeptideMeter2026-Q399.933.94Buyer-sourced0PASS
AX-2026-041474QYBQYB-2607-L4875VendorInvestigate2026-Q399.163.7895.6Buyer-sourced0PASS
AX-2026-041470QYBQYB-2607-L4875Janoshik2026-Q399.774.10Buyer-sourced0PASS
AX-2026-042139JEEPJEEP-2601-K8195VendorInvestigate2026-Q298.324.2999.4Buyer-sourced1FAIL
AX-2026-041964AMBAMB-2601-M5602Janoshik2026-Q299.933.20Buyer-sourced0PASS
AX-2026-041664FGPFGP-2602-Y8741Janoshik2026-Q299.904.48106.5Buyer-sourced0PASS
Other recent WXT records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043376SemaglutideWXT-2604-C3248Janoshik2026-Q397.084.22Buyer-sourced1MARGINAL
AX-2026-043429L-Glutathione (reduced)WXT-2605-B3833Nordanalyt2026-Q398.486.5896.9Supplier-supplied1FAIL
AX-2026-043347LeuprolideWXT-2604-K2596PeptideMeter2026-Q399.165.9993.6Buyer-sourced0PASS
AX-2026-043353LeuprolideWXT-2604-K2596Janoshik2026-Q399.194.9095.3Laboratory-retained0PASS
AX-2026-043345LeuprolideWXT-2604-K2596Janoshik2026-Q398.935.28Buyer-sourced0PASS
AX-2026-043424L-Glutathione (reduced)WXT-2605-B3833PeptideMeter2026-Q398.376.86Buyer-sourced0FAIL
AX-2026-043374SemaglutideWXT-2604-C3248Janoshik2026-Q397.003.56Buyer-sourced1MARGINAL
AX-2026-043377SemaglutideWXT-2604-C3248PeptideMeter2026-Q397.204.08Buyer-sourced1MARGINAL