AssayIndex

AX-2026-042677

Retatrutide · 10 mg declared · Nantong Guangyuan Chemical Co., Ltd. · lot GGPE-2510-R9180

MARGINALIDENTITY CONSISTENT
Report ID
AX-2026-042677
Compound
Retatrutide
Compound class
Incretin analogues and co-agonists
Supplier
GGPeps — Nantong Guangyuan Chemical Co., Ltd.
Batch / lot
GGPE-2510-R9180
Declared label claim
10mg
Laboratory
Medutest
Assay date
25 Mar 2026
Submitted
09 Apr 2026
Quarter
2026-Q1
Submitter
a.trevino
Sample provenance
Laboratory-retained
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 nm99.45% area≥ 96.5PASS
Total impuritiesRP-HPLC, sum of reported peaks0.55% area≤ 3.5PASS
Largest single impurityRP-HPLC — C18 diacid regioisomer0.35% area≤ 1.00PASS
Identity — theoretical monoisotopic masscalculated from molecular formula4728.4871Da—NOT TESTED
Identity — observed monoisotopic massLC-MS, unit resolution (single quadrupole)4728.4885Da—NOT TESTED
Mass accuracyobserved vs theoretical+0.3ppm± 15PASS
Total peptide contentby difference from the gravimetric mass balance88.07%w/w—NOT TESTED
Target-compound contenttotal peptide content × purity87.59%w/w—NOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen10.51mg10 mg declaredNOT TESTED
Recovered target peptidegross fill × target content9.206mg10 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim92.1%90.0 – 110.0PASS
Water contentKarl Fischer, coulometric, duplicate3.45%≤ 8.0PASS
Counter-ion (TFA)anion-exchange ion chromatography8.11%≤ 12.0PASS
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.37%—NOT TESTED
Endotoxinkinetic chromogenic LAL0.38EU/mg≤ 5.0PASS
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 after 90 s gentle swirling, no particulates—clear, no visible particulatesPASS
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration5.00—2.5 – 8.0PASS
Retention time (observed)RP-HPLC, 25 min gradient17.40min17.53 ± 0.50 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.461.10—0.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²56,692—≥ 20,000PASS
Resolution to nearest impurityvs C18 diacid regioisomer1.61—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.

01500300145016001 Retatrutide17.40 min · 99.45 % 17.8815.8019.41 same trace · ×200 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 56,692, and skew follows the reported asymmetry factor of 1.10. 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 0.35 % impurity against a 99.45 % 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 peak17.404,833,57899.45—
2C18 diacid regioisomer17.8817,0110.350.000
3incomplete Fmoc removal (+222 Da)19.413,8880.08+222.068
4truncated (5-39)15.803,4020.07-428.201
5aspartimide (−18 Da)17.992,4300.05-18.011
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 4728.4871 Da, computed from C221H342N46O68. All ppm figures on this site are against monoisotopic values — see why that matters.

0255075100550750950115013501550 [M+5H]5+946.71[M+6H]6+789.09[M+4H]4+1183.13 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 4728.4885 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+676.5054676.50560.00028.4
6+789.0885789.08870.000256.8
5+946.7047946.70500.0003100.0
4+1183.12911183.12940.000356.7
3+1577.16961577.17010.00059.2
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 Fischer3.45
Counter-ion (TFA)ion chromatography8.11
Residual solvent + inorganic residueestimated0.37
Total peptide contentby difference88.07
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)99.5499.45divergence +0.15 pp vs batch median
Total impurities (% area)0.460.55
Largest single impurity (% area)not stated0.35
Water (%)2.33.45
Counter-ion (%)not stated8.11
Peptide content (%w/w)not stated88.07
Endotoxin (EU/mg)not stated0.38
Method stated on certificateYES—column, 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, 20 d since original receipt) → re-assay.
Assay date
25 Mar 2026
Submitted to the index
09 Apr 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 GGPE-2510-R9180 n=14

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042671GGPE-2510-R9180Janoshik2026-Q199.763.3692.4Supplier-supplied1MARGINAL
AX-2026-042672GGPE-2510-R9180Kestrel2026-Q198.854.07—Supplier-supplied2MARGINAL
AX-2026-042673GGPE-2510-R9180PeptideMeter2026-Q198.874.41—Supplier-supplied2MARGINAL
AX-2026-042674GGPE-2510-R9180PeptideMeter2026-Q198.583.35—Supplier-supplied2MARGINAL
AX-2026-042675GGPE-2510-R9180PeptideMeter2026-Q199.233.2697.2Supplier-supplied1MARGINAL
AX-2026-042676GGPE-2510-R9180Janoshik2026-Q199.193.36—Supplier-supplied3MARGINAL
AX-2026-042678GGPE-2510-R9180Medutest2026-Q199.883.4189.0Supplier-supplied4MARGINAL
AX-2026-042679GGPE-2510-R9180Janoshik2026-Q199.333.10—Buyer-sourced1MARGINAL
AX-2026-042680GGPE-2510-R9180Nordanalyt2026-Q199.802.96—Supplier-supplied2MARGINAL
AX-2026-042681GGPE-2510-R9180Kestrel2026-Q199.852.79—Supplier-supplied1MARGINAL
AX-2026-042682GGPE-2510-R9180Janoshik2026-Q199.023.3698.4Supplier-supplied3FAIL
AX-2026-042683GGPE-2510-R9180Janoshik2026-Q199.673.39—Supplier-supplied1MARGINAL
AX-2026-042684GGPE-2510-R9180Janoshik2026-Q199.743.37—Supplier-supplied2MARGINAL

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 GGPeps records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042737SelankGGPE-2603-J9708Janoshik2026-Q398.409.1497.4Buyer-sourced0FAIL
AX-2026-042804SelankGGPE-2602-G2056Janoshik2026-Q398.507.97—Supplier-supplied0FAIL
AX-2026-042803SelankGGPE-2602-G2056Janoshik2026-Q398.488.01—Laboratory-retained1FAIL
AX-2026-042802SelankGGPE-2602-G2056Janoshik2026-Q398.747.0996.0Supplier-supplied0FAIL
AX-2026-042796SelankGGPE-2602-G2056Janoshik2026-Q398.267.5697.5Buyer-sourced0FAIL
AX-2026-042648Melanotan IIGGPE-2603-P8735Janoshik2026-Q399.106.97—Supplier-supplied4MARGINAL
AX-2026-042797SelankGGPE-2602-G2056Medutest2026-Q398.467.92—Buyer-sourced0FAIL
AX-2026-042669CJC-1295 (no DAC)GGPE-2606-E8495Medutest2026-Q398.614.0695.5Supplier-supplied0PASS