AssayIndex

AX-2024-004339

PT-141 (Bremelanotide) · 10 mg declared · Qingdao Sigma Chemical Co., Ltd. · lot QSC-2402-X7410

MARGINALPURITY ONLY
Report ID
AX-2024-004339
Compound
PT-141 (Bremelanotide)
Compound class
Melanocortin-receptor peptides
Supplier
QSC — Qingdao Sigma Chemical Co., Ltd.
Batch / lot
QSC-2402-X7410
Declared label claim
10mg
Laboratory
Janoshik Analytical
Assay date
17 Jan 2024
Submitted
11 Feb 2024
Quarter
2024-Q1
Submitter
pt141_one_da
Sample provenance
Supplier-supplied
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 nm99.80% area≥ 98.5PASS
Total impuritiesRP-HPLC, sum of reported peaks0.20% area≤ 1.5PASS
Largest single impurityRP-HPLC — linear precursor (+18 Da)0.12% area≤ 1.00PASS
Identitynot ordered on this submissionnot determinedrequired for VERIFIED statusNOT TESTED
Total peptide contentby difference from the gravimetric mass balance89.85%w/wNOT TESTED
Target-compound contenttotal peptide content × purity89.67%w/wNOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen9.91mg10 mg declaredNOT TESTED
Recovered target peptidegross fill × target content8.886mg10 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim88.9%90.0 – 110.0FAIL
Water contentKarl Fischer, coulometric, duplicate3.80%≤ 8.0PASS
Counter-ion (acetate)anion-exchange ion chromatography6.10%≤ 10.0PASS
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.25%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 to pale-yellow cake, intactwhite to off-white intact cakePASS
Reconstitution clarityreconstituted per submitter procedureClear, colourless, no visible particulatesclear, no visible particulatesPASS
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration5.602.5 – 8.0PASS
Retention time (observed)RP-HPLC, 30 min gradient9.51min9.52 ± 0.25 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.461.250.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²90,505≥ 20,000PASS
Resolution to nearest impurityvs melanotan II (C-terminal amide, −1 Da)2.47no 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.

032486497974512994 PT-141 (Bremelanotide)9.51 min · 99.80 % 8.81 same trace · ×200 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 90,505, and skew follows the reported asymmetry factor of 1.25. 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 0.12 % impurity against a 99.80 % 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 peak9.514,850,58999.80
2linear precursor (+18 Da)8.815,8320.12+18.011
3melanotan II (C-terminal amide, −1 Da)9.831,9440.04-0.984
4oxidised Trp (+16 Da)9.171,9440.04+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 Fischer3.80
Counter-ion (acetate)ion chromatography6.10
Residual solvent + inorganic residueestimated0.25
Total peptide contentby difference89.85
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)99.9099.80divergence +0.30 pp vs batch median
Total impurities (% area)not stated0.20
Largest single impurity (% area)not stated0.12
Water (%)3.13.80
Counter-ion (%)not stated6.10
Peptide content (%w/w)92.189.85
Endotoxin (EU/mg)not statednot determined
Method stated on certificateNOno 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, 8 d) → assay. Submitter did not handle the vial.
Assay date
17 Jan 2024
Submitted to the index
11 Feb 2024
Laboratory
Janoshik Analytical, Ostrava, Czechia
Method basis
30 min gradient · high-resolution MS
Verification status
PURITY ONLY
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 QSC-2402-X7410 n=12

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2024-004337QSC-2402-X7410Janoshik2024-Q199.503.5991.5Supplier-supplied0PASS
AX-2024-004338QSC-2402-X7410Kestrel2024-Q199.934.03102.6Supplier-supplied0PASS
AX-2024-004340QSC-2402-X7410Kestrel2024-Q199.933.5091.0Supplier-supplied0PASS
AX-2024-004341QSC-2402-X7410PeptideMeter2024-Q199.614.0693.2Supplier-supplied0PASS
AX-2024-004342QSC-2402-X7410VendorInvestigate2024-Q199.442.86Buyer-sourced0PASS
AX-2024-004343QSC-2402-X7410Nordanalyt2024-Q199.602.8794.7Supplier-supplied0PASS
AX-2024-004344QSC-2402-X7410VendorInvestigate2024-Q198.744.05Buyer-sourced0PASS
AX-2024-004345QSC-2402-X7410Janoshik2024-Q199.843.77Supplier-supplied0PASS
AX-2024-004346QSC-2402-X7410Janoshik2024-Q199.763.91Supplier-supplied0PASS
AX-2024-004347QSC-2402-X7410Janoshik2024-Q199.042.8798.5Laboratory-retained0PASS
AX-2024-004348QSC-2402-X7410PeptideMeter2024-Q199.352.8295.5Supplier-supplied0PASS
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 QSC records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041683CJC-1295 (no DAC)QSC-2606-V8637Janoshik2026-Q399.933.6397.1Supplier-supplied1FAIL
AX-2026-041727CJC-1295 with DACQSC-2602-E9474Janoshik2026-Q398.886.62105.3Supplier-supplied1MARGINAL
AX-2026-041728CJC-1295 with DACQSC-2602-E9474VendorInvestigate2026-Q398.427.04Buyer-sourced1MARGINAL
AX-2026-041734CJC-1295 with DACQSC-2602-E9474Medutest2026-Q399.437.17105.5Supplier-supplied2FAIL
AX-2026-041652LiraglutideQSC-2605-W8602Nordanalyt2026-Q399.336.55Supplier-supplied0PASS
AX-2026-041730CJC-1295 with DACQSC-2602-E9474PeptideMeter2026-Q398.796.9395.4Supplier-supplied1MARGINAL
AX-2026-041686CJC-1295 (no DAC)QSC-2606-V8637Janoshik2026-Q399.934.04Supplier-supplied0PASS
AX-2026-041653LiraglutideQSC-2605-W8602VendorInvestigate2026-Q398.825.95Buyer-sourced0PASS