AssayIndex

AX-2026-041876

Retatrutide · 30 mg declared · SinoPep Biotechnology (Changzhou) Co., Ltd. · lot SNP-2603-G4042

MARGINALPURITY ONLY
Report ID
AX-2026-041876
Compound
Retatrutide
Compound class
Incretin analogues and co-agonists
Supplier
SinoPep — SinoPep Biotechnology (Changzhou) Co., Ltd.
Batch / lot
SNP-2603-G4042
Declared label claim
30mg
Laboratory
Janoshik Analytical
Assay date
07 Feb 2026
Submitted
02 Mar 2026
Quarter
2026-Q1
Submitter
a.lundgren
Sample provenance
Buyer-sourced
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, 30 min gradient, 214 nm97.52% area≥ 96.5PASS
Total impuritiesRP-HPLC, sum of reported peaks2.48% area≤ 3.5PASS
Largest single impurityRP-HPLC — truncated (5-39)1.73% area≤ 1.00FAIL
Identitynot ordered on this submissionnot determinedrequired for VERIFIED statusNOT TESTED
Total peptide contentby difference from the gravimetric mass balance84.58%w/wNOT TESTED
Target-compound contenttotal peptide content × purity82.48%w/wNOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen32.68mg30 mg declaredNOT TESTED
Recovered target peptidegross fill × target content26.954mg30 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim89.8%90.0 – 110.0FAIL
Water contentKarl Fischer, coulometric, duplicate5.79%≤ 8.0PASS
Counter-ion (TFA)anion-exchange ion chromatography9.05%≤ 12.0PASS
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.58%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, colourless, no visible particulatesclear, no visible particulatesPASS
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration3.452.5 – 8.0PASS
Retention time (observed)RP-HPLC, 30 min gradient20.70min20.71 ± 0.50 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.461.070.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²66,194≥ 20,000PASS
Resolution to nearest impurityvs [D-Aib2]-diastereomer0.67no 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.

01356271140675423 Retatrutide20.70 min · 97.52 % 18.7823.1120.4824.82 same trace · ×20 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 66,194, and skew follows the reported asymmetry factor of 1.07. 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 1.73 % impurity against a 97.52 % 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 peak20.704,739,77497.52
2truncated (5-39)18.7884,0831.73-428.201
3incomplete Fmoc removal (+222 Da)23.1117,0110.35+222.068
4des-Aib20 analogue20.268,7490.18-85.053
5retatrutide dimer24.824,3740.09+4728.487
6[D-Aib2]-diastereomer20.483,8880.080.000
7oxidised Trp (+16 Da)20.042,4300.05+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 Fischer5.79
Counter-ion (TFA)ion chromatography9.05
Residual solvent + inorganic residueestimated0.58
Total peptide contentby difference84.58
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)97.2297.52divergence -0.36 pp vs batch median
Total impurities (% area)2.782.48
Largest single impurity (% area)1.231.73
Water (%)3.65.79
Counter-ion (%)7.59.05
Peptide content (%w/w)88.384.58
Endotoxin (EU/mg)0.84not 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 → third-party forwarder (1 d) → laboratory (courier, cold pack, 4 d) → assay.
Assay date
07 Feb 2026
Submitted to the index
02 Mar 2026
Laboratory
Janoshik Analytical, Ostrava, Czechia
Method basis
30 min gradient · high-resolution MS
Verification status
PURITY ONLY
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.

buyer_sourced
Anyone can generate one of these. That is the argument the index makes on its submission page and it is the reason the dataset grows without any supplier's cooperation.
epitalon_bAsp
A beta-aspartyl isomer sits a tenth of a minute away and is mass-identical. That is the archetype of a pair where resolution is a compound property and no rule should adjudicate it.
gc_headspace
Residual solvent occupies mass in the cake that is neither peptide, water nor counter-ion. On a freshly dried lot it can be a percent, and it is measured on very few records.
Section 7

Related records

Same batch — lot SNP-2603-G4042 n=12

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041869SNP-2603-G4042Nordanalyt2026-Q197.625.52101.1Buyer-sourced1MARGINAL
AX-2026-041870SNP-2603-G4042Janoshik2026-Q197.295.12Buyer-sourced1MARGINAL
AX-2026-041871SNP-2603-G4042Medutest2026-Q197.705.92103.4Buyer-sourced1MARGINAL
AX-2026-041872SNP-2603-G4042Janoshik2026-Q197.755.33106.2Buyer-sourced2FAIL
AX-2026-041873SNP-2603-G4042Kestrel2026-Q197.965.0697.2Buyer-sourced1MARGINAL
AX-2026-041874SNP-2603-G4042Janoshik2026-Q197.835.56Buyer-sourced1MARGINAL
AX-2026-041875SNP-2603-G4042VendorInvestigate2026-Q197.595.40Buyer-sourced1MARGINAL
AX-2026-041877SNP-2603-G4042Janoshik2026-Q197.525.67Buyer-sourced1FAIL
AX-2026-041878SNP-2603-G4042Nordanalyt2026-Q197.424.84Buyer-sourced1MARGINAL
AX-2026-041879SNP-2603-G4042Janoshik2026-Q197.565.5396.9Buyer-sourced1MARGINAL
AX-2026-041880SNP-2603-G4042Medutest2026-Q197.445.22Buyer-sourced1MARGINAL
Other recent Retatrutide records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042437HomopeptideHOMO-2605-V4718Nordanalyt2026-Q398.683.67102.8Buyer-sourced0PASS
AX-2026-043095KPKP-2607-H5774Janoshik2026-Q395.815.48105.2Buyer-sourced0FAIL
AX-2026-042282TFCTFC-2608-J1156Janoshik2026-Q398.544.27Buyer-sourced0PASS
AX-2026-043094KPKP-2607-H5774PeptideMeter2026-Q396.326.40Buyer-sourced0FAIL
AX-2026-042441HomopeptideHOMO-2605-V4718Medutest2026-Q398.934.22Buyer-sourced0PASS
AX-2026-041427QYBQYB-2604-B4920PeptideMeter2026-Q397.932.45101.7Buyer-sourced0PASS
AX-2026-041786ASYASY-{CAT}-2288VendorInvestigate2026-Q398.786.59Buyer-sourced0PASS
AX-2026-041428QYBQYB-2604-B4920Janoshik2026-Q398.353.20Laboratory-retained0PASS
Other recent SinoPep records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041867CJC-1295 with DACSNP-2607-C3886Janoshik2026-Q399.245.12Laboratory-retained1FAIL
AX-2026-041913IpamorelinSNP-2606-L4478PeptideMeter2026-Q398.885.28Buyer-sourced0FAIL
AX-2026-041914IpamorelinSNP-2606-L4478Janoshik2026-Q399.145.49Buyer-sourced0PASS
AX-2026-041909IpamorelinSNP-2606-L4478PeptideMeter2026-Q399.005.4889.5Buyer-sourced1MARGINAL
AX-2026-041895IpamorelinSNP-2602-B3833Janoshik2026-Q399.934.72105.9Buyer-sourced1MARGINAL
AX-2026-041930IGF-1 LR3SNP-2606-D4620Medutest2026-Q398.545.3793.8Buyer-sourced0PASS
AX-2026-041898IpamorelinSNP-2602-B3833Nordanalyt2026-Q399.934.5496.0Buyer-sourced1MARGINAL
AX-2026-041931IGF-1 LR3SNP-2606-D4620PeptideMeter2026-Q397.935.1993.4Buyer-sourced0PASS