Render5 mg vial · front

Incretin & glucagon receptors

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Retatrutide

A synthetic, lipidated 39-residue peptide that acts on three receptors: GIP, GLP-1 and glucagon.

Also known as LY3437943

Research use only Not an approved medicine

Formula: C₂₂₁H₃₄₂N₄₆O₆₈
Average mass: 4731.348 Da
Length: 39 residues

Lot Record

Sealed, crimp-capped vial with its lot number on the label.
Orders are packed once payment clears.

Research use only. Retatrutide is supplied as a laboratory reagent. It is not a drug, food, supplement or cosmetic, and it is not for human or veterinary use.

Lot record

Check the lot before you buy.

Purity is the main peak’s share of the HPLC signal. Identity is the mass the sequence predicts, next to the mass measured. Move along either trace to read it.

Certificate of analysis

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HPLC purity
Release minimum: 99.0%
Mass, calculated: 4731.348 Da
Mass, observed
Difference: release rule: within ±1.0 Da
Tested
Laboratory
Method

How to read a certificate

HPLC RP · UV 220 nm

The chromatogram draws here from the lot’s numbers.

Mass spec ESI, positive

The mass spectrum draws here from the sequence and the lot’s numbers.

Every published lot

Published lots of Retatrutide
Lot	Tested	HPLC purity	Observed mass, Da	Status	Certificate

Overview

What it is.

Retatrutide (LY3437943) is a 39-residue peptide with a C-terminal amide. Three of its residues are non-standard: 2-aminoisobutyric acid at positions 2 and 20, and α-methyl-L-leucine at position 13. The lysine at position 17 carries a C20 fatty diacid on a γ-glutamate and AEEA linker; the formula and masses shown include it.

It was developed by Eli Lilly as a single molecule that activates the GIP, GLP-1 and glucagon receptors, and has been studied in receptor-pharmacology, animal and clinical research. It is not an approved medicine.

We don’t summarize studies on product pages. Search PubMed for “Retatrutide” (opens in a new tab)

Sequence & properties

Computed from the sequence.

Y1Aib2Q3G4T5F6T7S8D9Y10S11I12αMeLeu13L14D15K16K17A18Q19Aib20A21F22I23E24Y25L26L27E28G29G30P31S32S33G34A35P36P37 P38S39

Lys17C20 diacid–γGlu–AEEASide-chain acylation: Eicosanedioic acid (C20 diacid) on γ-glutamate and AEEA

Residue colors: Hydrophobic Polar Basic (+) Acidic (−) Non-standard

Three-letter sequence: H-Tyr-Aib-Gln-Gly-Thr-Phe-Thr-Ser-Asp-Tyr-Ser-Ile-αMeLeu-Leu-Asp-Lys-Lys-Ala-Gln-Aib-Ala-Phe-Ile-Glu-Tyr-Leu-Leu-Glu-Gly-Gly-Pro-Ser-Ser-Gly-Ala-Pro-Pro-Pro-Ser-NH₂

Open in Sequence Studio

Molecular formula: C₂₂₁H₃₄₂N₄₆O₆₈
Average mass: 4731.348 Da
Monoisotopic mass: 4728.4718 Da
Length: 39 residues
Isoelectric point (pI): 3.73
Net charge at pH 7.0: −4.02
GRAVY (Kyte–Doolittle): −0.187
Extinction coefficient, 280 nm: 4,470 M⁻¹cm⁻¹
Modifications: C-terminal amide; Lys17 side-chain acylation (C20 diacid–γGlu–AEEA); contains non-standard residues
CAS number: 2381089-83-2
Form: Lyophilized powder in a sealed glass vial
Purity: Measured per lot by HPLC: see the lot record

Calculated from the sequence with standard atomic weights and the EMBOSS pKa set, for the free peptide (not a salt form). The formula, masses and charge include the side chain on Lys17. The formula matches a chemical supplier’s datasheet (opens in a new tab); the mass agrees with it to within 0.05 Da.

HydropathyKyte–Doolittle · window 7

Above zero is hydrophobic; below is polar or charged. Most hydrophobic stretch: residues 21–27 (average +1.7). Most polar: residues 15–21 (average −1.3). Windows above zero: 16 of 33. Kyte–Doolittle gives no value for Aib or αMeLeu, or for the acyl group on Lys17. Here and in GRAVY, Aib is scored as Ala (+1.8), αMeLeu as Leu (+3.8) and Lys17 as plain Lys (−3.9).

Storage & handling

Cold, dry and dark.

Sealed vial: Follow the released lot’s documented storage conditions and laboratory safety data.
In transit: Transport conditions must be supported for this material; ambient shipping is not assumed.
Before opening: Let the vial reach room temperature, so moisture doesn’t condense on the powder.
In solution: Use a validated in-vitro laboratory protocol. Stability depends on the compound, solvent and conditions; no general shelf life is promised.

Solution Calculator Storage and handling guide

Questions

Before you order.

All questions

How do I know what’s in the vial?

Every lot we sell has a certificate of analysis on file, showing HPLC purity and mass-spectrometry identity for that exact lot. It is linked on the product page before you buy.

The lot number printed on your vial opens the same record on our Verify page, so you can match the vial in your hand to its test results.

What does an HPLC purity figure tell me?

High-performance liquid chromatography separates a sample into its components. Purity is the main peak’s share of the total detected signal, usually measured by UV absorbance around 214–220 nm.

It measures the main component against peptide-related impurities; it isn’t net peptide content, which also accounts for water and counter-ions.

What HPLC purity means

How do I pay, and when does my order ship?

The available payment methods are listed at checkout. A research request first enters review, with no payment due. Payment instructions appear only after verification and approval. Sample requests cannot be paid or fulfilled.

Orders are packed once payment clears. You can follow every step on the order page or with your order number on Track an order.

What does “research use only” mean?

Our peptides are supplied as laboratory reagents for research by qualified buyers. None is approved as a drug, food, supplement or cosmetic in the form we supply it, and none is for human or veterinary use.

We don’t give advice about using peptides in people or animals, and product pages describe what each compound is and how it is studied, never what it does to a person.