Product Details
HGH Frag 176-191 (AOD-9604) — Research Grade Peptide, ≥98% Purity (HPLC)
Synthetic hGH C-terminal fragment. Lipolysis research tool. Lyophilized powder. Lot-specific COA included.
HGH Frag 176-191 is a synthetic 16-amino acid peptide corresponding to the C-terminal region (residues 176–191) of human growth hormone (hGH). The sequence is H-Tyr-Leu-Arg-Ile-Val-Gln-Cys-Arg-Ser-Val-Glu-Gly-Ser-Cys-Gly-Phe-OH, with a disulfide bridge between the cysteine residues at positions 7 and 14. The peptide was engineered to isolate the lipolytic activity of hGH while avoiding its growth-promoting and glucose-regulating effects, and it does not bind the growth hormone receptor or elevate IGF-1 levels.
The compound is closely related to AOD-9604, which is the same 176–191 sequence with a tyrosine residue added at the N-terminus, producing a 177–191 fragment modified for longer duration and a different safety profile. The two names are often used interchangeably in vendor catalogs, but the distinction matters for documentation. HGH Frag 176-191 is the parent sequence; AOD-9604 is the stabilized, lab-engineered version that underwent clinical development.
The peptide’s research profile centers on its proposed action at adipose tissue, where it is thought to stimulate beta-3 adrenergic receptors and promote lipolysis while inhibiting lipogenesis. However, the FDA’s 2024 evaluation noted that the molecular targets and mechanisms behind its pharmacological effects remain uncertain, and the pivotal human trial failed to demonstrate clinically meaningful weight loss.
Supplied as a sterile-filtered, lyophilized powder for in vitro and preclinical research applications. Each lot is independently verified for purity and identity and ships with a Certificate of Analysis.
Specifications
| Parameter | Detail |
|---|---|
| CAS Number (free base) | 66004-57-7 |
| Molecular Formula | C₇₈H₁₂₃N₂₃O₂₂S₂ (free base); C₇₈H₁₂₅N₂₃O₂₃S₂ (as listed by some suppliers) |
| Molecular Weight | 1799.1 g/mol (free base); 1815.08 g/mol (alternate listing) |
| Sequence | H-Tyr-Leu-Arg-Ile-Val-Gln-Cys-Arg-Ser-Val-Glu-Gly-Ser-Cys-Gly-Phe-OH (Disulfide bridge: Cys7–Cys14) |
| Purity | ≥98% (HPLC) |
| Identity | Confirmed by mass spectrometry |
| Appearance | White to off-white lyophilized powder |
| Solubility | Soluble in water and aqueous buffers |
| Storage | −20 °C, desiccated, protected from light |
| Format | Lyophilized powder, sterile-filtered |
| Documentation | Lot-specific COA (HPLC + MS) |
Note: Suppliers list HGH Frag 176-191 with varying molecular weights and formulas because the product is offered in free base, acetate, and trifluoroacetate (TFA) salt forms. PubChem lists the free base at 1799.1 g/mol. Some suppliers list 1815.08 g/mol, which corresponds to a different salt form or calculation. Verify the exact form and molecular weight against the Certificate of Analysis supplied with your lot.
Research applications
HGH Frag 176-191 is used in laboratory settings to investigate:
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Lipolysis and lipogenesis research — proposed beta-3 adrenergic receptor-mediated effects on fat breakdown and storage in adipocyte cell culture models
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hGH fragment pharmacology — comparative study of the 176–191 fragment versus full-length hGH for metabolic effects in in vitro systems, with studies showing a short-lived rise in blood glucose and a more sustained rise in plasma insulin in rats
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Insulin sensitivity research — a single dose (5 nmol/kg body weight) of peptides containing the 178–191 sequence significantly reduced insulin sensitivity in intravenous insulin tolerance tests
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Cancer research applications — enhancement of doxorubicin-loaded chitosan nanoparticle toxicity against MCF-7 breast cancer cells, with in silico analysis suggesting the fragment enhances doxorubicin binding to multiple breast cancer protein targets
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Adipose tissue metabolism — lipid metabolism pathways and their regulation in isolated adipocytes and adipose tissue explants
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Analytical method development — LC-MS/MS quantification and reference standard preparation for hGH fragment analysis
Handling and storage
Reconstitute under aseptic conditions using sterile water or an appropriate aqueous buffer. HGH Frag 176-191 is soluble in water. Aliquot immediately after reconstitution to avoid repeated freeze-thaw cycles. Lyophilized powder is stable for up to 2 years at −20 °C under sealed, desiccated, light-protected conditions. Reconstituted solutions should be stored at 2–8 °C and used within 14–21 days. Do not freeze reconstituted solution.
For laboratory use by qualified personnel only.




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Fast shipping and excellent peptide quality. Packaging was discreet and professional.
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Batch-specific COA included and product quality was top-notch. Highly recommend.
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