If you have been reading about human growth hormone and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-09-30. Numbers and descriptions here follow the published literature rather than marketing material.
AOD-9604 is prohibited in sport by the World Anti-Doping Agency under the peptide hormone class. Its presence in a sample can be detected through mass spectrometry-based methods, although the exact assay depends on the laboratory. In research settings, material is often supplied as a lyophilized powder for reconstitution. Buyers and researchers should note that products labeled AOD-9604 may vary in purity and actual peptide content. Analytical certificates and independent testing are common ways to verify identity, but no global harmonized standard exists for all commercial lots.
AOD-9604 is a synthetic peptide whose sequence is modeled on the C-terminal region of human growth hormone. Published descriptions commonly place it as a modified fragment corresponding to hGH amino acids 176–191, with a tyrosine residue added or retained at the N-terminus to support detection and handling. It is not intact growth hormone and lacks the full receptor-binding architecture of the parent protein. The molecule was developed as a research candidate for metabolic studies rather than as a replacement for growth hormone therapy. Its identity is defined by its amino acid sequence rather than by any single commercial preparation.
Quality varies among research-grade suppliers, so certificates of analysis and independent testing are important for verification. A typical certificate reports purity by HPLC, identity by mass spectrometry, appearance, and sometimes residual solvents or water content. AOD9604 is often sold as a research chemical not intended for human consumption, and labels can be inaccurate. Common misconceptions include treating the peptide as a form of growth hormone, assuming supplement status, or expecting approved-drug quality from unregulated products.
AOD9604 is commonly supplied as a white to off-white lyophilized powder. The powder is typically stored at -20 °C or below, protected from light and moisture, because peptides can degrade through oxidation, hydrolysis, or aggregation. If it is reconstituted for laboratory use, an appropriate aqueous buffer or solvent is chosen, and the solution is kept cold and handled to avoid repeated freeze-thaw cycles. These practices support stability but do not imply suitability for human use.
Identity and purity are usually assessed with reversed-phase high-performance liquid chromatography and mass spectrometry. Reversed-phase HPLC separates the peptide from related impurities and can estimate purity by ultraviolet absorbance, while mass spectrometry confirms the molecular mass and detects modifications. Peptide mapping, amino acid analysis, and disulfide mapping may be used when the sequence or disulfide arrangement must be verified. Because AOD9604 contains cysteine residues, oxidation and disulfide isomers are possible quality concerns in synthetic batches.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic peptide | Fragment analog of human growth hormone |
| Sequence basis | hGH 176–191 region | Modified C-terminal fragment |
| Common synonyms | AOD-9604; AOD9604; hGH fragment | Research and trade names vary |
| Regulatory status | Not approved as a drug | Prohibited in competitive sport |
| Research code | AOD9604 | Used in scientific and patent literature |
Early interest in AOD-9604 centered on whether a fragment of human growth hormone could influence fat metabolism without the broader effects of the full hormone. Cell and animal studies reported changes in fat storage and breakdown. Human trials followed, but the results were not strong enough to secure regulatory approval. The compound remains available for laboratory research, and its clinical potential is still described as uncertain. Studies continue to examine its activity and safety profile.
AOD-9604 is a synthetic peptide that corresponds to a short section of human growth hormone. It is commonly identified as hGH fragment 176-191 because its sequence matches residues at the C-terminal end of the hormone. The molecule contains sixteen amino acids and is made by solid-phase peptide synthesis. Researchers study it for metabolic effects rather than for the growth-promoting actions associated with full human growth hormone. Its small size distinguishes it from the complete 191-amino-acid hormone.
Several names appear in scientific and commercial settings. AOD9604 and AOD-9604 are development codes used interchangeably, while hGH fragment 176-191 describes the same region. The peptide includes a disulfide bond between two cysteine residues, which helps shape its three-dimensional structure. Different suppliers may provide acetate or other salt forms, and purity can vary. These differences matter because analytical tests and biological assays can respond to the specific form being studied.
Research has examined whether the peptide affects fat mass independently of growth hormone's other actions. Early animal studies suggested reductions in body fat, but species differences and small sample sizes limit interpretation. Human studies have generally been short and have not consistently shown large effects. Some trials measured body composition, lipid profiles, and safety parameters, but the overall picture is one of suggestive yet inconclusive metabolic activity. Findings vary across study populations and protocols.
A central uncertainty is whether observed metabolic changes translate into meaningful clinical benefits. Study designs vary in dose, duration, and participant characteristics, making comparisons difficult. Independent replication is limited, and the field lacks consensus on optimal endpoints or treatment duration. Ongoing or future studies may clarify mechanism and effect size, but current evidence does not establish a clear therapeutic role. Researchers often call for larger, longer, and better-controlled trials, while questions remain about which patient groups might respond.
Proposed mechanism focuses on lipolysis, the breakdown of stored triglycerides into free fatty acids and glycerol. AOD-9604 is thought to act on adipose tissue without stimulating appetite or affecting blood sugar in the same way as growth hormone. Laboratory studies report increased fat oxidation in some models. The precise receptor interactions and signaling pathways remain incompletely characterized. Researchers have proposed that the peptide may influence fat mobilization through pathways distinct from the full hormone.
AOD-9604 has been investigated mainly in the context of body fat and metabolic endpoints. Some early animal and small human studies reported changes in fat mass or lipid markers, but findings were not uniform. Larger, well-controlled trials that would establish efficacy are lacking in the public literature. As a result, claims about weight loss or metabolic benefit remain investigational rather than established. The distinction between a research finding and a proven clinical outcome is central to discussing this peptide.
Regulatory bodies have taken different approaches to AOD-9604. It is not approved as a prescription medicine by major agencies such as the U.S. Food and Drug Administration or the European Medicines Agency. In sport, the World Anti-Doping Agency prohibits peptide hormones, growth factors, and related substances, and AOD-9604 has been treated as a prohibited substance. These regulatory decisions reflect concerns about safety, efficacy, and potential misuse rather than proof of benefit.
Xylazine binds at a ratio of 160:0, the lowest of all α2-adrenergic receptor agonists and 1/10th of that of medetomidine and dexmedotimidine. Xylazine is less selective than the other α2-Adrenergic receptor agonists. The analgesic effect of xylazine comes from binding to receptors at the substantia gelatinosa and locus coeruleus.
Major Charles Karu Singleton, The Princess of Wales's Royal Regiment, 565366. Staff Sergeant Charlotte Louise Spence, Royal Army Physical Training Corps, W1060016. Major Jonathan Grant Studwell, Intelligence Corps, 30170101. Major Thomas Daniel Sweeney, Army Air Corps, 24757307. Sergeant Edward William Swindell, , Corps of Royal Engineers, Army Reserve, 30150063. Major Francesca Louise Sykes, Royal Regiment of Artillery, 30067880. Lieutenant Colonel Andrew James Teeton, Corps of Royal Engineers, 536346. Major (now Acting Lieutenant Colonel) James Viney, Corps of Royal Engineers, 25185183. Captain (now Acting Major) David Edward Williams, Corps of Royal Electrical and Mechanical Engineers, 24929032. Master Aircrew Oliver Martin Dewey, Royal Air Force, 30060196. Sergeant (now Acting Flight Sergeant) George Joseph Downey, Royal Air Force, L8516771. Wing Commander Sam Haley, Royal Air Force, 30000089. Squadron Leader James Duncan Hemingfield, Royal Air Force, 8700294K. Sergeant Martin John Henderson, Royal Air Force, 30112261. Squadron Leader Sharon Ingle, Royal Air Force, 30091084. Flight Sergeant (now Acting Warrant Officer) Stewart Marcus Jackson, Royal Air Force, F8427999. Flight Sergeant Philip Kipling, Royal Air Force, D8411323. Squadron Leader Kevin Charles William March, Royal Air Force, 30035301. Squadron Leader Christopher Scott Middleton, Royal Air Force, 2642751S. Squadron Leader Mark Shipley, Royal Air Force, 30001963. Warrant Officer Garry John Stanton, Royal Air Force, K8421673.
During the retention period, specimens are considered part of the medical record and must be kept in a CLIA-accredited laboratory to ensure compliant handling and storage conditions. If a specimen is sent out to a non-CLIA biorepository and recalled, the additional testing would not be in compliance. There is an effort to make more biobanks CLIA equivalent as specimen recalls become more common due to expanded testing.
In 1991, a group of Russian chemistry students discovered a simplified synthesis route which used phosgene instead of phenethylamine. Soon, abuse of the drug became widespread, causing a tenth of overdoses in the Moscow region.
== Etymology == The historical origin of the term is unclear as the definition of the word has changed throughout the past few decades. The term first appeared in a 1984 publication that described the organization of an endothelium-like membrane on the surface of a long-implanted, synthetic ophthalmic prosthesis. The first modern use of the term as recognized today was in 1985 by the researcher, physiologist and bioengineer Yuan-Cheng Fung of the Engineering Research Center. He proposed the joining of the terms tissue (in reference to the fundamental relationship between cells and organs) and engineering (in reference to the field of modification of said tissues). The term was officially adopted in 1987.
Sources: en.wikipedia.org
=== Water purification === NASA engineers are collaborating with qualified companies to develop systems intended to sustain the astronauts living on the International Space Station and future Moon and space missions. This system turns wastewater from respiration, sweat, and urine into drinkable water. By combining the benefits of chemical adsorption, ion exchange, and ultra-filtration processes, this technology can yield safe, drinkable water from the most challenging sources, such as in underdeveloped regions where well water may be heavily contaminated.
It is believed the first tulips in the United States were grown near Spring Pond at the Fay Estate in Lynn and Salem, Massachusetts. From 1847 to 1865, Richard Sullivan Fay, Esq., one of Lynn's wealthiest men, settled on 2 km2 (200 ha; 500 acres) located partly in present-day Lynn and partly in present-day Salem. Mr. Fay imported many different trees and plants from all parts of the world and planted them among the meadows of the Fay Estate.
=== Judges' Costumes === Episode 1: Carla Hall as a neuroscientist with an exposed brain, Stephanie Boswell as a chemist mutated by a chemical spill, and Zac Young as a beaker of green slime Episode 2: Carla Hall as a victim of an exploding stand mixer, Stephanie Boswell as a victim of killer macarons, and Zac Young as a victim of a sprinkles allergy Episode 3: Carla Hall as a creepy psychedelic bunny, Stephanie Boswell as a cutesy bunny, and Zac Young as a monstrous bunny Episode 4: Carla Hall as a skeleton lady, Stephanie Boswell as a mummy influencer, and Zac Young as Mummy Dearest Episode 5: Carla Hall as a house's front door, Stephanie Boswell as a tornado, and Zac Young as a cow Episode 6: Carla Hall as a headless demon, Stephanie Boswell as the nosey neighbor from Hades, and Zac Young as a goat demon Episode 7: Carla Hall as a were-chicken, Stephanie Boswell as a reanimated lady, and Zac Young as a vampire agent
=== Structure-activity-relationship (SAR) === An important part of designing a compound, that is an ideal inhibitor to a certain target, is to understand the amino acid sequence of the target site for the compound to bind to. Modelling both prothrombin and FXa makes it possible to deduct the difference and identify the amino acids at each binding site. At the bottom of the S1 pocket on FXa the binding amino acid is Asp-189 which amidine moieties can bind to. After X-raying the binding site of FXa, it was revealed that the S1 pocket had a planar shape, meaning that a flat amidinoaryl group should bind to it without steric hindrance. Modern direct Xa inhibitors are L-shaped molecules whose ends fit perfectly in the S1 and S4 pockets. The long side of the L-shape has to conform to a highly-specific tunnel within the targets active site. To accomplish that, this part of the molecules is designed to have little formal interactions with FXa in that region. As there is no specific bonding, the fit of these agents between the pockets of FXa increases the total specificity of the drugs to the FXa molecule. The interaction between the S1 pocket of FXa and the inhibitor can be both ionic or non-ionic, which is important because it allows the design of the moiety to be adjusted to increase oral bioavailability. Previously designed compounds were charged molecules that are not absorbed well in the gastrointestinal tract and therefore did not reach high serum concentrations.
A diphenylamine (DPA) indicator will confirm the presence of DNA. This procedure involves chemical hydrolysis of DNA: when heated (e.g. ≥95 °C) in acid, the reaction requires a deoxyribose sugar and therefore is specific for DNA. Under these conditions, the 2-deoxyribose is converted to w-hydroxylevulinyl aldehyde, which reacts with the compound, diphenylamine, to produce a blue-colored compound. DNA concentration can be determined by measuring the intensity of absorbance of the solution at the 600 nm with a spectrophotometer and comparing to a standard curve of known DNA concentrations. Measuring the intensity of absorbance of the DNA solution at wavelengths 260 nm and 280 nm is used as a measure of DNA purity. DNA can be quantified by cutting the DNA with a restriction enzyme, running it on an agarose gel, staining with ethidium bromide (EtBr) or a different stain and comparing the intensity of the DNA with a DNA marker of known concentration. Using the Southern blot technique, this quantified DNA can be isolated and examined further using PCR and RFLP analysis. These procedures allow differentiation of the repeated sequences within the genome. It is these techniques which forensic scientists use for comparison, identification, and analysis.
Sources: en.wikipedia.org
No. It is a synthetic peptide fragment modeled on part of human growth hormone, not the full hormone. It does not contain the complete sequence or receptor-binding regions of hGH.
It was investigated in clinical trials for obesity, but it did not receive approval for that use in major markets. Results were generally modest or mixed, and it remains an experimental compound.
WADA lists it as a prohibited peptide hormone. Its use can be detected by laboratory methods, and athletes are subject to sanctions if it is found in samples.
Lyophilized AOD9604 is generally kept at -20 °C or colder, desiccated, and protected from light. Reconstituted solutions are usually refrigerated and handled to minimize repeated freeze-thaw cycles. These are general laboratory handling practices, not instructions for human use.