AssayIndex

AX-2026-042165

Retatrutide · 5 mg declared · Hunan Aslsen Technology Co., Ltd. · lot HOMO-2601-J8878

FAILIDENTITY CONSISTENT
Report ID
AX-2026-042165
Compound
Retatrutide
Compound class
Incretin analogues and co-agonists
Supplier
Homopeptide — Hunan Aslsen Technology Co., Ltd.
Batch / lot
HOMO-2601-J8878
Declared label claim
5mg
Laboratory
Medutest
Assay date
31 Jan 2026
Submitted
14 Feb 2026
Quarter
2026-Q1
Submitter
i.demir
Sample provenance
Supplier-supplied
Section 1

Results

Measured against the index acceptance specification for the incretin analogues and co-agonists 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 nm98.88% area≥ 96.5PASS
Total impuritiesRP-HPLC, sum of reported peaks1.12% area≤ 3.5PASS
Largest single impurityRP-HPLC — des-Aib20 analogue0.55% area≤ 1.00PASS
Identity — theoretical monoisotopic masscalculated from molecular formula4728.4871Da—NOT TESTED
Identity — observed monoisotopic massLC-MS, unit resolution (single quadrupole)4728.4497Da—NOT TESTED
Mass accuracyobserved vs theoretical-7.9ppm± 15PASS
Total peptide contentby difference from the gravimetric mass balance87.76%w/w—NOT TESTED
Target-compound contenttotal peptide content × purity86.78%w/w—NOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen5.75mg5 mg declaredNOT TESTED
Recovered target peptidegross fill × target content4.990mg5 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim99.8%90.0 – 110.0PASS
Water contentKarl Fischer, coulometric, duplicate5.25%≤ 8.0PASS
Counter-ion (TFA)anion-exchange ion chromatography6.21%≤ 12.0PASS
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.78%—NOT TESTED
Endotoxinkinetic chromogenic LAL5.37EU/mg≤ 5.0FAIL
Sterilitynot ordered on this submissionnot determined—no growthNOT TESTED
Appearancevisual, diffuse light, black and white backgroundWhite lyophilised cake, intact—white to off-white intact cakePASS
Reconstitution clarityreconstituted per submitter procedureClear, colourless, no visible particulates—clear, no visible particulatesPASS
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration3.69—2.5 – 8.0PASS
Retention time (observed)RP-HPLC, 25 min gradient17.56min17.53 ± 0.50 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.461.18—0.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²62,738—≥ 20,000PASS
Resolution to nearest impurityvs [D-Aib2]-diastereomer0.64—no 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.

01498299644945992 Retatrutide17.56 min · 98.88 % 17.1919.57 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 62,738, and skew follows the reported asymmetry factor of 1.18. 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 0.55 % impurity against a 98.88 % main peak is a line two pixels tall; the main peak runs off-scale there by design.
#PeakRTArea (µV·s)% areaΔ mass (Da)
1Retatrutide — main peak17.564,805,87598.88—
2des-Aib20 analogue17.1926,7320.55-85.053
3C18 diacid regioisomer18.0417,4970.360.000
4[D-Aib2]-diastereomer17.386,3180.130.000
5aspartimide (−18 Da)18.152,4300.05-18.011
6incomplete Fmoc removal (+222 Da)19.571,4580.03+222.068
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 4728.4871 Da, computed from C221H342N46O68. All ppm figures on this site are against monoisotopic values — see why that matters.

0255075100550750950115013501550 [M+5H]5+946.70[M+6H]6+789.08[M+4H]4+1183.12 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 4728.4497 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 (%)
7+676.5054676.5001-0.00538.3
6+789.0885789.0822-0.006353.4
5+946.7047946.6972-0.0075100.0
4+1183.12911183.1197-0.009449.3
3+1577.16961577.1572-0.01248.5
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 Fischer5.25
Counter-ion (TFA)ion chromatography6.21
Residual solvent + inorganic residueestimated0.78
Total peptide contentby difference87.76
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)99.1598.88divergence +0.26 pp vs batch median
Total impurities (% area)0.851.12
Largest single impurity (% area)0.450.55
Water (%)not stated5.25
Counter-ion (%)6.46.21
Peptide content (%w/w)89.587.76
Endotoxin (EU/mg)2.215.37
Method stated on certificateNO—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, 7 d) → assay. Submitter did not handle the vial.
Assay date
31 Jan 2026
Submitted to the index
14 Feb 2026
Laboratory
Medutest, Ljubljana, Slovenia
Method basis
25 min gradient · unit-resolution MS
Verification status
IDENTITY CONSISTENT
Section 6

Annotations 4

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.

lal_assay
5.37 EU/mg is above the index screening threshold of 5.0. Two things to keep separate: the index threshold is a screening figure, and a real limit is dose-dependent. The endotoxin dose-limit calculator does that arithmetic. What this record establishes is that the burden is measurable and high relative to the rest of the dataset.
baseline_noise
Endotoxin determined but the LAL method is not stated. Kinetic chromogenic and gel-clot give different results and different sensitivity. The value cannot be interpreted without knowing which.
ash_sulfated
No endotoxin figure on this record, which is true of roughly three quarters of the index. It is the one measurement that cannot be inferred from any other and the one most often omitted.
multiple_compare
5.37 EU/mg is elevated relative to the index median and the record shows no depyrogenation step. If this material will be reconstituted in aqueous buffer for any downstream use, that endotoxin load is a risk.
Section 7

Related records

Same batch — lot HOMO-2601-J8878 n=4

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042162HOMO-2601-J8878Janoshik2026-Q198.824.76—Supplier-supplied2FAIL
AX-2026-042163HOMO-2601-J8878Kestrel2026-Q199.814.85—Supplier-supplied1MARGINAL
AX-2026-042164HOMO-2601-J8878Janoshik2026-Q198.895.1997.1Supplier-supplied1MARGINAL

Cross-sections

Other recent Retatrutide records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043029KPKP-2607-H5219Medutest2026-Q395.455.71—Supplier-supplied2FAIL
AX-2026-043030KPKP-2607-H5219Kestrel2026-Q395.976.9597.1Supplier-supplied2FAIL
AX-2026-041453QYBQYB-2604-B5660VendorInvestigate2026-Q398.022.55—Buyer-sourced1MARGINAL
AX-2026-041454QYBQYB-2604-B5660Janoshik2026-Q398.842.77—Supplier-supplied1MARGINAL
AX-2026-041538QYBQYB-2602-G6308Medutest2026-Q398.502.85—Supplier-supplied2MARGINAL
AX-2026-041456QYBQYB-2604-B5660Janoshik2026-Q398.233.24—Supplier-supplied1MARGINAL
AX-2026-041452QYBQYB-2604-B5660Nordanalyt2026-Q398.503.36—Supplier-supplied1MARGINAL
AX-2026-043039KPKP-2607-H5219Janoshik2026-Q396.145.62—Supplier-supplied2FAIL
Other recent Homopeptide records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042181IpamorelinHOMO-2608-A9045Janoshik2026-Q399.784.79—Supplier-supplied1MARGINAL
AX-2026-042172SemaglutideHOMO-2604-X8921Janoshik2026-Q399.645.1691.9Supplier-supplied1MARGINAL
AX-2026-042278SLU-PP-332HOMO-2602-Y2822Kestrel2026-Q399.714.42—Supplier-supplied0PASS
AX-2026-042180IpamorelinHOMO-2608-A9045Janoshik2026-Q399.394.74105.5Supplier-supplied1MARGINAL
AX-2026-042184IpamorelinHOMO-2608-A9045Kestrel2026-Q399.274.79103.2Supplier-supplied1MARGINAL
AX-2026-042274SLU-PP-332HOMO-2602-Y2822VendorInvestigate2026-Q398.714.72—Laboratory-retained0PASS
AX-2026-042183IpamorelinHOMO-2608-A9045VendorInvestigate2026-Q399.384.97—Buyer-sourced1MARGINAL
AX-2026-042194RetatrutideHOMO-2605-V9833PeptideMeter2026-Q398.904.0798.8Supplier-supplied3MARGINAL