Certificate of analysis: Retatrutide, batch ATRET-10-2511-01
Retatrutide, batch ATRET-10-2511-01, tested by the independent laboratory Analyton Labs, certificate AN-2026-00001 issued 22 September 2026: purity 99.23 ± 0.20 % by RP-HPLC, 9.94 mg peptide per vial, trifluoroacetate not detected, bacterial endotoxins < 0.001 EU/mg, 19 determinations in total.
- Product
- Retatrutide
- Batch
- ATRET-10-2511-01
- Certificate number
- AN-2026-00001
- Laboratory
- Analyton Labs
- Issued
- Sample
- Retatrutide, lyophilised powder, vial labelled 10 mg
Summary of results, 19 determinations
Methods and results are given in English exactly as recorded by the laboratory.
| Determination | Method | Result | Specification |
|---|---|---|---|
| Appearance | Visual | White to off-white powder | White to off-white powder |
| Identity | LC-HRMS (ESI+), USP <621> principles | Deconvoluted monoisotopic mass 4728.47 Da, deviation 0.4 ppm; observed m/z 1577.16 (3+) and 1183.13 (4+) | Theoretical monoisotopic 4728.472 Da from C221H342N46O68, expected m/z 1577.165 (3+), 1183.125 (4+) |
| Purity | RP-HPLC, C18, 214 nm, area % | 99.23 ± 0.20 % (k = 2) | >= 98.0 % |
| Related substances | RP-HPLC, 214 nm; LOD 0.01 %, LOQ 0.03 %, reporting threshold 0.05 % | Largest single impurity 0.23 % at RRT 1.03 (± 0.03 %); total impurities 0.77 %, i.e. 0.077 mg per vial | Single <= 1.0 %, total <= 2.0 % |
| Impurity profile | RP-HPLC with LC-HRMS assignment | RRT 0.93, 0.11 %, -18 Da (Asp succinimide); RRT 0.97, 0.19 %, same mass (isoAsp at Asp9 or Asp15); RRT 1.03, 0.23 %, +0.98 Da (deamidation of Gln3 or Gln18); RRT 1.08, 0.14 %, +16 Da (Tyr oxidation); RRT 1.15, 0.10 %, -18 Da (Asp15 succinimide) | Peaks above 0.05 % reported (ICH Q3B) |
| Net peptide content | Assay | 95.4 ± 1.2 % w/w (k = 2) | |
| Fill weight | Gravimetric | 10.42 ± 0.05 mg | Labelled 10 mg |
| Peptide per vial | Calculated from fill weight and net peptide content | 9.94 mg per vial labelled 10 mg, i.e. 99.4 % of label | 95 to 105 % of label |
| Counter-ion content | Ion chromatography (cation) | Sodium 1.10 % w/w (± 0.08 %), i.e. 0.11 mg per vial | <= 5.0 % |
| Trifluoroacetate | Ion chromatography, LOQ 20 ppm | Not detected | <= 1000 ppm |
| Water content | Coulometric Karl Fischer, USP <921> | 2.80 ± 0.15 % w/w (k = 2), i.e. 0.29 mg per vial | <= 8.0 % |
| Mass balance | Peptide + counter-ion + water | 95.40 + 1.10 + 2.80 = 99.30 % (± 1.2 %) | Close to 100 % |
| pH | Potentiometric, 10 mg/ml in water | 6.8 | 6.0 to 7.6 |
| Solubility | Visual, 10 mg/ml and 1 mg/ml | >= 10 mg/ml in water and in bacteriostatic water; clear, colourless, free of particles within 30 s. Lipidated peptide: dissolve at pH 7.5, opalescent below pH 6 | Clear solution |
| Bacterial endotoxins | Kinetic chromogenic LAL, USP <85> | < 0.001 EU/mg (< 0.01 EU per vial) | <= 10 EU/mg |
| Sterility | Membrane filtration, USP <71>; fluid thioglycollate 30 to 35 °C and soya bean casein digest 20 to 25 °C | No growth after 14 days, 2 vials | No growth |
| Residual solvents | Headspace GC, USP <467> | Acetonitrile 45 ppm; N,N-dimethylformamide, methanol, dichloromethane, diethyl ether, diisopropyl ether and piperidine each < 10 ppm (LOQ 10 ppm) | ICH Q3C: acetonitrile <= 410, DMF <= 880, methanol <= 3000, dichloromethane <= 600, ethers <= 5000 ppm |
| Elemental impurities | ICP-MS after microwave digestion (HNO3/H2O2), USP <233> | Cd, Pb, As, Hg < 0.05 µg/g; Co, V, Ni < 0.10 µg/g, all below LOQ | ICH Q3D(R2) Class 1 and 2A, parenteral PDE |
| Chiral purity (D-amino acids) | Acid hydrolysis (6 M DCl in D2O, 110 °C, 24 h), Marfey's derivatisation (FDAA), LC-MS | D-Asp 0.12 %, D-Ser 0.08 %, D-Glu 0.05 %, D-Tyr 0.04 %, others < 0.05 %; alpha-methyl-Leu < 0.05 %; Aib achiral; sum of D-forms 0.29 % | Each D-amino acid <= 0.2 %, sum of D-forms <= 0.5 % |
File SHA-256: 59aee78cac7195e3c2847fe111308eb1c4c75f6e37c8e4c8f0a1175c14cd63a5
Research material. The certificate describes the properties of the batch, not suitability for any use in humans or animals.
