If you have been reading about mass spectrometry 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 2026-04-15. Numbers and descriptions here follow the published literature rather than marketing material.
Regulatory treatment of AOD-9604 has varied. In sports anti-doping, the peptide became widely discussed during a 2013 investigation into an Australian professional sports club. Authorities at the time debated whether it fell under prohibitions on growth hormone and related substances. Later clarifications and updated lists have addressed the compound in different ways. Anyone seeking current status should consult the latest applicable rules, and commercial supply for human use is not authorized in major markets.
Research interest in AOD-9604 often focuses on whether it can influence lipid metabolism without the growth-promoting or glucose-related effects of full-length hGH. This question remains unresolved, and findings depend on model, dose, and measurement method. Some reviews treat the peptide as a historical obesity candidate rather than an active therapeutic. Others cite it in discussions of peptide fragments, metabolic signaling, and performance-enhancing substances. Clear conclusions are limited by the small number of rigorous, independent human studies.
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.
| Property | Value | Notes |
|---|---|---|
| Primary research area | Obesity and metabolic regulation | Studied in cell, animal, and human models |
| Highest reported trial phase | Phase II | Public summaries describe mixed results |
| Common route in trials | Subcutaneous injection | Typical for peptide therapeutics |
| Regulatory example | 2013 Australian anti-doping review | Classification was debated at the time |
| Approval status | Not approved as a human medicine | Status can change by jurisdiction |
Detection of AOD-9604 in biological samples relies on analytical techniques capable of distinguishing a small synthetic peptide from related endogenous sequences. Liquid chromatography coupled with tandem mass spectrometry is commonly used for confirmatory analysis. Sample preparation may involve immunoaffinity enrichment or solid-phase extraction to concentrate the peptide. Because the molecule is small and may be present at low concentrations, assay sensitivity and specificity are ongoing analytical challenges. Laboratories also validate methods against reference materials when available.
Regulatory interest in AOD-9604 increased after high-profile anti-doping cases involving peptide products. In some cases, the substance was supplied under alternative names or in compounded preparations, complicating traceability. Sports tribunals and anti-doping panels have discussed whether the peptide was explicitly banned at the time of use, leading to clarifications by the World Anti-Doping Agency. For consumers and researchers, the legal status can vary by jurisdiction, and products marketed as research chemicals may lack independent quality verification.
In laboratory settings, AOD-9604 is commonly supplied as a lyophilized powder and stored cold to limit degradation. Reconstituted solutions are typically kept refrigerated or frozen, depending on the buffer and concentration, and protected from repeated freeze-thaw cycles. Stability can be influenced by pH, temperature, and the presence of proteases. Purity is usually assessed by high-performance liquid chromatography and mass spectrometry. These practices support reproducibility, but they do not imply safety or efficacy for any human use.
Regulatory status: AOD-9604 is not approved as a therapeutic drug in the United States, European Union, or other major markets. It is listed by the World Anti-Doping Agency as a prohibited substance in sport, specifically under growth hormone fragments. Many jurisdictions restrict its sale for human consumption. Products marketed online may not meet pharmaceutical quality standards. The legal status varies by country and often depends on whether the material is presented as a research chemical, supplement, or drug.
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.
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.
Heterolytic fragmentation is bond cleavage where the bonding electrons remain with only one of the fragment species. In CID, charge remote fragmentation is a type of covalent bond breaking that occurs in a gas phase ion in which the cleaved bond is not adjacent to the location of the charge. This fragmentation can be observed using tandem mass spectrometry.
=== Distribution === With oral CPA, there is a probable distribution phase of CPA into tissues which lasts about 12 hours and has a half-life of 3 hours. CPA is very lipophilic, and it is sequestered into fat, which provides a depot effect. The volume of distribution of CPA is 20.6 ± 3.5 L/kg. CPA crosses the blood–brain barrier, which is evidenced by the suppression of gonadotropin secretion that is observed during therapy with it (the site of action of this effect being the pituitary gland, a part of the brain). In terms of plasma protein binding, CPA does not bind to SHBG or corticosteroid-binding globulin and is instead bound exclusively to albumin (93%), with the remainder (7%) circulating free or unbound. The affinity of CPA for SHBG is very low at about 0.006% of that of testosterone or DHT.
In 2022, the University of North Carolina established two student awards in his name, funded in part by gifts from Wadden and his sister, Anne Wadden Peck: one for training in clinical and health psychology and another for distinguished research in behavioral medicine and health psychology.
=== Water filtration === Given the water adsorption properties of silica gel, it is used in domestic water filters. The surface structure of silica gel allows the adsorption of some minerals that are dissolved in the water, or "ion exchange" as it is marketed. Due to the lack of regulations for domestic water filtration products, no studies validate the manufacturer claims regarding the effectiveness of the filtration system.
==== Anti-scatter grid ==== An anti-scatter grid is a device in X-ray technology that is placed in front of the image receiver (screen, detector, or film) and reduces the incidence of diffuse radiation on it. The first diffusion radiation grid was developed in 1913 by Gustav Peter Bucky (1880-1963). The US radiologist Hollis Elmer Potter (1880-1964) improved it in 1917 by adding a moving device. The radiation dose must be increased when using scattered radiation grids. For this reason, the use of scattered radiation equipment should not be used on children. In digital radiography, a grid may be omitted under certain conditions to reduce radiation exposure to the patient.
Sources: en.wikipedia.org
=== Artificial === De novo designed peptides which self-assemble in the presence of copper (Cu), forming supramolecular assemblies were presented by Korendovych et al. Additionally there are examples of metallopeptides that are, at least partially, composed of non-natural amino acids with possible applications in drug discovery and biomaterials.
Although they have been determined to be receptors to certain ligands from opioids, their role is not yet fully understood. When opioids are ingested, the ligand binds to these constitutively active receptors to reduce neural activity. This is accomplished by inhibiting adenylyl cyclase and cyclic AMP, which are necessary for communication within the central nervous system. There is research indicating that opioids reduce pain by disrupting ion channels and vesicle fusion. Prolonged exposure to opioids can cause these receptors to become internalized, leading to increased tolerance and increased opioid use.
In Weeds episode "Lude Awakening" the character Celia Hodes, portrayed by actress Elizabeth Perkins, states, "I hold in my hand the last Quaalude on earth. See you around, girls." Season 18 of Law & Order: Special Victims Unit addresses Quaalude administration as a date rape drug in episode 9, "Decline and Fall", which aired January 18, 2017. In the first season of True Detective, Rust Cohle's use of Quaaludes is briefly mentioned in several episodes. It is also used by Patrick Melrose in Edward St Aubyn's 1992 novel Bad News. In the 2024 film Maria, Maria Callas, played by Angelina Jolie, stuffs Mandrax into the pockets of her coats and bags so that she'll be able to escape detection by her butler/guardian Ferruccio (Pierfrancesco Favino). The 2000 novel House of Leaves by Mark Z. Danielewski features the supporting character named Lude, referencing Quaaludes. In the 2026 song, Burning Bridges by rapper Drake, he references the substance with the lyric "I'm off a Quay, it make my body tingle”.
== Notes == An α indicates the medicine is on the complementary list for which specialized diagnostic or monitoring or training is needed. An item may also be listed as complementary on the basis of higher costs or a less attractive cost-benefit ratio.
Sources: en.wikipedia.org
No major medicines regulator appears to have approved AOD-9604 for human therapeutic use. It has been studied in clinical trials, but those programs did not result in a marketed drug.
It became prominent during a 2013 Australian sports investigation that examined whether it was a prohibited growth-hormone-related substance. Subsequent interpretations and list updates have varied, so current rules should be checked directly.
Published summaries generally report limited or inconsistent weight-loss effects, and complete trial data are not widely available. The studies were not sufficient to establish it as an effective obesity treatment.
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.