The research compound retatrutide has an empirical molecular formula of C221H342N46O68 and a monoisotopic molecular weight of approximately 4731.33 g/mol (4731.33 Da). As a synthetic 39-amino-acid peptide conjugated with a C20 fatty diacid moiety, it serves as a triple agonist targeting GIP, GLP-1, and glucagon receptors in preclinical laboratory models.
The research compound retatrutide has an empirical molecular formula of C221H342N46O68 and a monoisotopic molecular weight of approximately 4731.33 g/mol (4731.33 Da). As a synthetic 39-amino-acid peptide conjugated with a C20 fatty diacid moiety, it serves as a triple agonist targeting GIP, GLP-1, and glucagon receptors in preclinical laboratory models.
In analytical chemistry and preclinical peptide profiling, precise determination of molecular specs is foundational for mass spectrometry (MS) calibration, high-performance liquid chromatography (HPLC) quantitative assays, and structural verification. Retatrutide (LY3437943) represents a novel class of multi-receptor agonists engineered for advanced metabolic signaling studies.
The complete chemical parameters for laboratory-grade retatrutide standard include:
• Chemical Formula: C221H342N46O68 • Molecular Weight: 4731.33 g/mol (Da) • CAS Registry Number: 2381089-83-2 • Structural Class: Synthetic acylated peptide amide (GIP/GLP-1/Glucagon receptor tri-agonist) • Sequence Length: 39 amino acid residues • Chemical Modification: C20 diacid acylation conjugated at Lys17 via a gamma-Glu-2xOEG linker
Researchers evaluating structural identity rely on accurate mass determinations to verify synthesized peptide lots. In high-resolution electrospray ionization mass spectrometry (ESI-MS), retatrutide yields multicharged molecular ion states (such as [M+4H]4+ and [M+5H]5+) corresponding to its theoretical mass of 4731.33 Da. Detailed documentation of these physical constants is essential when sourcing analytical standards via our research hub.
The primary sequence of retatrutide is derived from the gastric inhibitory polypeptide (GIP) backbone, modified systematically to confer balanced potency across three distinct G-protein coupled receptors: GIPR, GLP-1R, and GCGR. Understanding the primary amino acid sequence enables investigators to map receptor-binding domains and enzymatic degradation resistance.
The single-letter amino acid sequence of retatrutide is structured as follows: Y-Aib-QGTFTSDYSKYLDEQKAKEFVQWLLAQK-NH2 (with specific side-chain acylation at Lys17)
Key structural attributes of this molecular sequence include: 1. Position 2 Substitution: Alpha-aminobutyric acid (Aib) is incorporated at position 2 to protect the N-terminal residue against rapid cleavage by dipeptidyl peptidase-4 (DPP-4). 2. C20 Fatty Diacid Acylation: A C20 diacid chain is attached to the epsilon-amino group of Lysine at position 17 using a bis-aminoethoxyethoxyacetyl-gamma-glutamyl (gamma-Glu-2xOEG) spacer. This hydrophobic side chain facilitates reversible binding to serum albumin, substantially extending the peptide's circulating half-life in preclinical animal models. 3. C-Terminal Amidation: The carboxyl terminus is amidated (-NH2) to optimize structural stability and mimic endogenous peptide signaling dynamics.
To explore complementary sequence structures or order high-purity material for comparative mass spectrometry, view our complete catalog of all research peptides.
In vitro receptor activation assays demonstrate that retatrutide functions as a potent, fully synthetic triple agonist. Preclinical cell-line assays measuring cyclic AMP (cAMP) accumulation report EC50 values that define its relative potencies across human GIP, GLP-1, and glucagon receptors:
• GIP Receptor (GIPR): Displays equal or greater potency compared to native GIP, initiating robust downstream metabolic signaling cascades. • GLP-1 Receptor (GLP-1R): Exhibits sub-nanomolar potency, driving intracellular signaling pathways involved in glucose-dependent insulin secretion in vitro. • Glucagon Receptor (GCGR): Shows balanced activation relative to native glucagon, facilitating lipolysis and energy expenditure pathways in preclinical rodent models.
By simultaneously engaging three distinct G-protein coupled receptors, retatrutide provides a unique pharmacological tool for investigating synergistic metabolic pathways. Researchers comparing multi-agonist kinetics often evaluate this compound alongside dual-agonist structures using our specialized retatrutide research peptides documentation.
When designing comparative in vitro or animal studies, researchers frequently compare retatrutide against single and dual incretin receptor mimetics to isolate specific receptor contributions. Distinct structural features, molecular weights, and side-chain lipidations govern their underlying pharmacokinetic profiles.
For example, while retatrutide features a 39-amino-acid backbone with a C20 diacid side chain, tirzepatide is a 39-amino-acid dual GIP/GLP-1 agonist featuring a C20 mono-acid lipidation at Lys20 and a molecular weight of 4813.45 Da. Conversely, semaglutide is a 31-amino-acid mono-GLP-1 agonist with a C18 fatty acid chain (MW 4113.58 Da). For researchers studying non-incretin pathways, co-formulation assays often compare these agents with amylin analogs like cagrilintide.
Understanding these precise chemical variations—such as C20 diacid vs. C18 mono-acid modifications—is critical when performing quantitative LC-MS/MS assay development or receptor binding kinetics experiments.
Retatrutide presents as a white to off-white lyophilized powder possessing high chemical purity when synthesized under controlled solid-phase peptide synthesis (SPPS) parameters. Proper handling in laboratory settings requires knowledge of its solubility, pI, and aggregation tendencies.
Important physical and chemical parameters include: • Isoelectric Point (pI): Estimated at ~4.2–4.7 based on acidic amino acid residues (Glu, Asp) and side-chain modifications. • Theoretical Isoelectric Neutrality: Retatrutide exhibits optimal solubility in slightly alkaline aqueous buffers (pH 7.4–8.0). • Lipophilicity: The presence of the C20 diacid acyl group imparts hydrophobic characteristics, requiring careful solvent selection during stock solution preparation to prevent non-specific surface adsorption.
When preparing stock solutions for cell culture or enzymatic assays, scientists should use sterile buffers such as phosphate-buffered saline (PBS, pH 7.4) or 0.1% BSA-supplemented diluents to minimize glass vial adsorption. Detailed liquid preparation instructions are available on our dedicated retatrutide product page.
To ensure reproducible data in laboratory experimentation, research compounds must undergo rigorous analytical verification before deployment. PX1 Research subjects every batch of retatrutide to a comprehensive testing matrix in ISO 17025 accredited analytical facilities.
Our standard analytical quality metrics require: 1. Reversed-Phase HPLC (RP-HPLC): Purity verification showing ≥99.0% main peak area purity, ensuring minimal truncated or deletion sequence impurities. 2. Electrospray Ionization Mass Spectrometry (ESI-MS): Exact molecular mass verification confirming the observed [M+H]+ spectrum aligns precisely with the theoretical 4731.33 Da mass. 3. Endotoxin Testing (LAL Assay): Chromogenic Limulus Amebocyte Lysate assay ensuring bacterial endotoxin levels remain below 0.01 EU/mg, protecting cell culture systems from lipopolysaccharide (LPS) contamination.
Every standard shipped by PX1 Research includes a lot-specific Certificate of Analysis (COA) detailing raw chromatographic data. Laboratories requiring high-volume supplies for ongoing trials can apply through our wholesale lab portal.
Proper reconstitution technique is vital to preserve the tertiary structural integrity of acylated peptides and prevent self-aggregation. Retatrutide lyophilized powder should be reconstituted using standardized laboratory protocols.
Recommended step-by-step reconstitution methodology: 1. Equilibrium: Allow the sealed peptide vial to reach room temperature (20°C–25°C) before opening to minimize moisture condensation onto the lyophilized cake. 2. Solvent Selection: Reconstitute with sterile bacteriostatic water (0.9% benzyl alcohol) or sterile isotonic saline, depending on the requirements of downstream assays. 3. Diluent Addition: Gently stream the diluent along the inner glass wall of the vial rather than shooting it directly onto the lyophilized powder. 4. Dissolution: Swirl the vial with gentle rotational movements. Do not vortex vigorously, as mechanical shear stress can induce protein denaturation or aggregation of the acylated side-chain.
For detailed calculations on volumetric concentration mapping, consult our retatrutide reconstitution calculator guide.
Peptide stability depends strictly on temperature control and moisture prevention. Retatrutide lyophilized powder exhibits long-term stability when stored under sub-zero conditions within sealed desiccated containers.
Laboratory storage protocols specify: • Lyophilized Cake (-20°C to -80°C): Stable for up to 24 months when stored protected from light in a manual-defrost freezer. • Reconstituted Liquid Stock (2°C to 8°C): Stable for up to 28 days when reconstituted with bacteriostatic water. For short-term assays using non-preserved buffers, use within 24–48 hours. • Aliquoting: To prevent degradation caused by repeated freeze-thaw cycles, reconstitute the master batch, aliquot into single-use polypropylene microtubes, and freeze at -80°C.
Understanding these thermodynamic stability parameters ensures consistent baseline performance across longitudinal animal models or cell culture trials. For broad comparative studies, review our metabolic research peptide overview.
PX1 Research is dedicated to supplying North American research institutions, university laboratories, and private biotech firms with verified analytical standards. Every batch of retatrutide is manufactured in GMP-compliant facilities within the United States, upholding strict quality control oversight.
Why leading laboratories trust PX1 Research: • USA Manufacturing: Synthesized under rigorous quality management systems in domestic facilities. • Lot Traceability: Every vial is assigned a unique lot identifier linked directly to its corresponding HPLC chromatogram and ESI-MS spectrum. • Accelerated Cold-Chain Shipping: Orders ship same-day (Monday through Friday) from fulfillment hubs in California and Arizona to guarantee thermal integrity upon delivery.
When conducting high-precision molecular characterization or receptor binding profiling, select PX1 Research for batch-to-batch consistency and total analytical transparency.
What is the retatrutide molecular formula molecular weight?
Retatrutide has an empirical molecular formula of C221H342N46O68 and a theoretical monoisotopic molecular weight of 4731.33 g/mol (4731.33 Da).
What is the amino acid sequence of retatrutide?
Retatrutide consists of a 39-amino-acid backbone: Y-Aib-QGTFTSDYSKYLDEQKAKEFVQWLLAQK-NH2, featuring a C20 fatty diacid acyl side chain conjugated at Lysine 17 via a gamma-Glu-2xOEG linker.
What is the CAS registry number for retatrutide?
The CAS registry number for retatrutide is 2381089-83-2.
How does retatrutide differ structurally from tirzepatide?
Retatrutide is a triple agonist targeting GIPR, GLP-1R, and GCGR with a molecular weight of 4731.33 Da and a C20 diacid at Lys17. Tirzepatide is a dual GIP/GLP-1 agonist with a molecular weight of 4813.45 Da and a C20 mono-acid at Lys20.
How should retatrutide be reconstituted for laboratory use?
Reconstitute retatrutide by slowly adding sterile bacteriostatic water or isotonic saline along the vial's inner wall. Swirl gently to dissolve; avoid vigorous vortexing to prevent peptide shearing and aggregation.
What purity level does PX1 Research guarantee for retatrutide?
PX1 Research guarantees ≥99.0% purity as verified by reversed-phase HPLC and ESI mass spectrometry for every lot.
What are the endotoxin limits for PX1 Research retatrutide?
Every lot undergoes chromogenic LAL testing to ensure bacterial endotoxin levels are strictly less than 0.01 EU/mg.
How should lyophilized retatrutide be stored in the lab?
Lyophilized retatrutide powder should be stored at -20°C or -80°C in a desiccated container protected from light. Reconstituted aliquots should be frozen at -80°C to avoid repeated freeze-thaw cycles.
Is retatrutide soluble in standard laboratory buffers?
Yes, retatrutide dissolves readily in neutral to slightly alkaline aqueous buffers (pH 7.4–8.0) like PBS or sterile saline. The addition of 0.1% BSA helps prevent non-specific surface binding in plasticware.
Where does PX1 Research manufacture and ship retatrutide from?
PX1 Research synthesizes retatrutide in US-based GMP-compliant facilities and fulfills orders same-day (M–F) from distribution centers in California and Arizona.
All products are sold strictly for laboratory and research use only. Not for human or veterinary use, diagnosis, treatment or consumption. Statements have not been evaluated by the FDA.