Everything below concerns mass spectrometry. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-02-07. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
AOD-9604 is listed as a prohibited substance in sport by the World Anti-Doping Agency. It falls under the peptide hormones, growth factors, related substances, and mimetics class on the prohibited list. Anti-doping organizations treat its presence in an athlete's sample as an adverse finding unless a therapeutic use exemption applies. The prohibition reflects concerns about performance enhancement in competitive settings and the difficulty of distinguishing exogenous peptide use from endogenous hormone fragments.
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.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Prohibited in sport | Listed by WADA under peptide hormones |
| WADA class | S2 | Peptide hormones, growth factors, related substances, and mimetics |
| Approved therapeutic use | Not established | Clinical research did not lead to broad marketing approval |
| Common detection method | LC-MS/MS | Liquid chromatography-tandem mass spectrometry |
| Sample preparation | Extraction and enrichment | Immunoaffinity or solid-phase extraction may be used |
Clinical development of AOD-9604 included trials in people with obesity. Reports from early-phase and mid-phase studies described modest or inconsistent changes in body weight. A phase IIb program did not meet its primary endpoint, and the compound was not approved for medical use. Differences in formulation, delivery route, and participant characteristics may explain some of the variation. Later investigations explored whether the peptide might have effects in other tissues, including cartilage.
Regulatory treatment of AOD-9604 is shaped by its classification as a peptide hormone. The World Anti-Doping Agency lists it as a prohibited substance, and many national anti-doping organizations adopt that list. It does not hold approval as a prescription medicine in the United States, the European Union, or other major markets. Products sold online are frequently labeled for research use only and may not undergo independent quality testing. Import and possession rules differ by country, so legal status depends on local law.
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.
AOD-9604 drew attention in the 1990s and 2000s as a potential anti-obesity agent. Early work explored both injectable and oral routes, which is unusual for a peptide of this size. Animal studies reported changes in fat metabolism without the growth-promoting or insulin-like effects associated with full-length growth hormone. Subsequent human trials produced mixed or modest results, and the compound did not obtain regulatory approval for weight management in major markets. It remains known mainly through research literature, sports anti-doping listings, and non-approved supplement advertising.
AOD-9604 is typically supplied as a lyophilized white to off-white powder. In this form, it is relatively stable when kept cool, dry, and protected from light. Common storage recommendations place it at −20 °C or below for long-term retention. Reconstituted solutions are less stable and are often kept at 2–8 °C for short periods. Freeze-thaw cycles should be minimized because they can promote aggregation or loss of peptide content. Vials are usually sealed under inert gas to reduce oxidation.
Identity and purity are commonly checked with reversed-phase high-performance liquid chromatography and mass spectrometry. RP-HPLC separates the peptide from related impurities and can estimate purity by peak area. Mass spectrometry confirms molecular mass and helps detect sequence variants or truncations. Some laboratories use amino acid analysis or peptide mapping for additional characterization. No single method proves biological activity; these techniques establish chemical identity and purity only. They also require suitable reference standards for confident comparison.
Commercial AOD-9604 may vary in purity, counterion content, and residual moisture. Certificates of analysis often report HPLC purity, mass confirmation, and appearance, but testing methods differ between suppliers. Independent verification is sometimes used because labeled content may not match actual peptide amount. Stability under different pH and temperature conditions is not fully standardized across studies. Researchers generally treat lyophilized material as the reference form for weighing and reconstitution. Moisture content can affect accurate mass measurement.
Caffeine withdrawal can cause mild to clinically significant distress or impairment in daily functioning. The frequency at which this occurs is self-reported at 11%, but in lab tests only half of the people who report withdrawal actually experience it, casting doubt on many claims of dependence. Mild physical dependence and withdrawal symptoms may occur upon abstinence, with greater than 100 mg caffeine per day, although these symptoms last no longer than a day. Some symptoms associated with psychological dependence may also occur during withdrawal. The diagnostic criteria for caffeine withdrawal require a previous prolonged daily use of caffeine. Following 24 hours of a marked reduction in consumption, a minimum of 3 of these signs or symptoms is required to meet withdrawal criteria: difficulty concentrating (reflecting reversal of the neuroadapted state), depressed mood/irritability, flu-like symptoms, headache, and fatigue. Additionally, the signs and symptoms must disrupt important areas of functioning and are not associated with effects of another condition. The ICD-11 includes caffeine dependence as a distinct diagnostic category, which closely mirrors the DSM-5's proposed set of criteria for "caffeine-use disorder". Caffeine use disorder refers to dependence on caffeine characterized by failure to control caffeine consumption despite negative physiological consequences.
== History == Before SHG was used for imaging, the first demonstration of SHG was performed in 1961 by P. A. Franken, G. Weinreich, C. W. Peters, and A. E. Hill at the University of Michigan, Ann Arbor using a quartz sample. In 1968, SHG from interfaces was discovered by Bloembergen and has since been used as a tool for characterizing surfaces and probing interface dynamics. In 1971, Fine and Hansen reported the first observation of SHG from biological tissue samples. In 1974, Robert W. Hellwarth and Christensen first reported the integration of SHG and microscopy by imaging SHG signals from polycrystalline ZnSe. In 1977, Colin Sheppard imaged various SHG crystals with a scanning optical microscope. The first biological imaging experiments were done by Freund and Deutsch in 1986 to study the orientation of collagen fibers in rat tail tendon. In 1993, Lewis examined the second-harmonic response of styryl dyes in electric fields. He also showed work on imaging live cells. In 2006, Goro Mizutani group developed a non-scanning SHG microscope that significantly shortens the time required for observation of large samples, even if the two-photons wide-field microscope was published in 1996 and could have been used to detect SHG. The non-scanning SHG microscope was used for observation of plant starch, megamolecule, spider silk and so on. In 2010 SHG was extended to whole-animal in vivo imaging. In 2019, SHG applications widened when it was applied to the use of selectively imaging agrochemicals directly on leaf surfaces to provide a way to evaluate the effectiveness of pesticides.
Collagen alpha-1(VIII) chain is a protein that in humans is encoded by the COL8A1 gene. This gene encodes one of the two alpha chains of type VIII collagen. The gene product is a short chain collagen and a major component of the basement membrane of the corneal endothelium. The type VIII collagen fibril can be either a homo- or a heterotrimer. Alternatively spliced transcript variants encoding the same isoform have been observed.
While some diseases like lupus exhibit familial aggregation, suggesting a genetic predisposition, other cases have been associated with infectious triggers or exposure to environmental factors, implying a complex interplay between genes and environment in their etiology. Some of the most common diseases that are generally categorized as autoimmune include coeliac disease, type 1 diabetes, Graves' disease, inflammatory bowel diseases (such as Crohn's disease and ulcerative colitis), multiple sclerosis, alopecia areata, Addison's disease, pernicious anemia, psoriasis, rheumatoid arthritis, and systemic lupus erythematosus. Diagnosing autoimmune diseases can be challenging due to their diverse presentations and the transient nature of many symptoms. Treatment modalities for autoimmune diseases vary based on the type of disease and its severity. Therapeutic approaches primarily aim to manage symptoms, reduce immune system activity, and maintain the body's ability to fight diseases. Nonsteroidal anti-inflammatory drugs (NSAIDs) and immunosuppressants are commonly used to reduce inflammation and control the overactive immune response. In certain cases, intravenous immunoglobulin may be administered to regulate the immune system. Despite these treatments often leading to symptom improvement, they usually do not offer a cure and long-term management is often required. In terms of prevalence, a UK study found that 10% of the population were affected by an autoimmune disease. Women are more commonly affected than men.
Components of the ECM are produced intracellularly by resident cells and secreted into the ECM via exocytosis. Once secreted, they then aggregate with the existing matrix. The ECM is composed of an interlocking mesh of fibrous proteins and glycosaminoglycans (GAGs).
Sources: en.wikipedia.org
== Treatment for collagen loss == Some of the causatives that break down collagen include spending too much time in the sun, smoking, dehydration, and stress. Thus, loss of collagen can be prevented via dietary changes, which may increase the turnover of cells and increase the creation of collagen, as well as lifestyle changes, including applying an adequate amount of sunscreen to prevent UV rays from the sun from damaging the skin and partaking in stress-relieving activities. Other interventions, such as taking vitamins C and A, can provide a boost to collagen production in the body. Consuming nutritious foods rich in the necessary vitamins, minerals, and amino acids promotes collagen production and reduces cellular damage within the body.
There are 19 known americium isotopes and 11 nuclear isomers, having mass numbers 229 through 247. There are two long-lived alpha-emitters; 243Am has a half-life of 7,350 years and is the most stable isotope, and 241Am has a half-life of 432.6 years. The most stable nuclear isomer is 242m1Am – generally called simply 242mAm – with a long half-life of 141 years. The half-lives of other isotopes and isomers are much shorter with a maximum of 50.8 hours for 240Am. As with most other actinides, the isotopes of americium with odd number of neutrons have relatively high fissionability with thermal neutrons and low critical mass. Americium-241 decays to 237Np emitting alpha particles of several different energies, mostly at 5.486 MeV (85.2%) and 5.443 MeV (12.8%). Because the resulting states are metastable, gamma rays are also emitted at discrete energies between 26.3 and 158.5 keV, by far the strongest is at 59.5 keV. The ground state of Americium-242 is a short-lived isotope with a half-life of 16.02 h. It mostly (82.7%) converts by β-decay to 242Cm, but also by electron capture to 242Pu (17.3%). Nearly all (99.55%) of the metastable 242mAm decays by internal conversion to 242Am and the remaining 0.45% by α-decay to 238Np. Americium-243 transforms by α-emission into 239Np.
=== Lawsuits === According to analysts from UBS, 13,000 suits had been filed by March 2010. Included among those suing: Santa Clara County, California, which claims to have spent $2 million on rosiglitazone between 1999 and 2007 at its public hospital and is asking for "triple damages". In May 2010, GlaxoSmithKline (GSK) reached settlement agreements for some of the cases against the company, agreeing to pay $60 million to resolve 700 suits. In July 2010, GSK reached settlement agreements to close another 10,000 of the lawsuits against it, agreeing to pay about $460 million to settle these suits.
== Discovery of optical activity == In 1843, Louis Pasteur discovered optical activity in paratartaric, or racemic, acid found in grape wine. He separated two enantiomer crystals that rotated polarized light in opposite directions.
Sources: en.wikipedia.org
Genentech pioneered the use of recombinant human growth hormone for human therapy, which was approved by the FDA in 1985. Prior to its production by recombinant DNA technology, growth hormone used to treat deficiencies was extracted from the pituitary glands of cadavers. Attempts to create a wholly synthetic HGH failed. Limited supplies of HGH resulted in the restriction of HGH therapy to the treatment of idiopathic short stature. Very limited clinical studies of growth hormone derived from an Old World monkey, the rhesus macaque, were conducted by John C. Beck and colleagues in Montreal, in the late 1950s. The study published in 1957, which was conducted on "a 13-year-old male with well-documented hypopituitarism secondary to a crainiophyaryngioma," found that: "Human and monkey growth hormone resulted in a significant enhancement of nitrogen storage ... (and) there was a retention of potassium, phosphorus, calcium, and sodium. ... There was a gain in body weight during both periods. ... There was a significant increase in urinary excretion of aldosterone during both periods of administration of growth hormone. This was most marked with the human growth hormone. ... Impairment of the glucose tolerance curve was evident after 10 days of administration of the human growth hormone.
The ONDCP stated in April 2011 that there had been a 46% drop in cocaine use among young adults over the previous five years, and a 65% drop in the rate of people testing positive for cocaine in the workplace since 2006. At the same time, a 2007 study found that up to 35% of college undergraduates used stimulants not prescribed to them. A 2013 study found that prices of heroin, cocaine and cannabis had decreased from 1990 to 2007, while the purity of these drugs had increased. The National Survey on Drug Use and Health for 2019 found that 1.7% of US adults over 25 had used cocaine in the previous 12 months, compared to 1.8% in 2002, and cannabis use went from 7% in 2002 to 15.2%. The DEA's 2021 National Drug Threat Assessment stated that "a steady supply of cocaine was available throughout domestic markets" in 2019 and 2020. According to the Centers for Disease Control (CDC), drug abuse fatalities in 2021 reached an all-time high of 108,000 deaths, a 15% increase from 2020 (93,000) which, at the time, was the highest number of deaths and a 30% increase from 2019. During alcohol prohibition, from 1920 to 1933, alcohol use initially fell but began to increase as early as 1922. It has been extrapolated that even if prohibition had not been repealed in 1933, alcohol consumption would have surpassed pre-prohibition levels. One argument against the war on drugs is that it uses similar measures as Prohibition and is no more effective.
Metabolomics is the scientific study of chemical processes involving metabolites, the small molecule substrates, intermediates, and products of cell metabolism. Specifically, metabolomics is the "systematic study of the unique chemical fingerprints that specific cellular processes leave behind", the study of their small-molecule metabolite profiles. The metabolome represents the complete set of metabolites in a biological cell, tissue, organ, or organism, which are the end products of cellular processes. Messenger RNA (mRNA), gene expression data, and proteomic analyses reveal the set of gene products being produced in the cell, data that represents one aspect of cellular function. Conversely, metabolic profiling can give an instantaneous snapshot of the physiology of that cell, and thus, metabolomics provides a direct "functional readout of the physiological state" of an organism. There are indeed quantifiable correlations between the metabolome and the other cellular ensembles (genome, transcriptome, proteome, and lipidome), which can be used to predict metabolite abundances in biological samples from, for example mRNA abundances. One of the ultimate challenges of systems biology is to integrate metabolomics with all other -omics information to provide a better understanding of cellular biology.
Sources: en.wikipedia.org
Yes, the World Anti-Doping Agency classifies AOD-9604 as a prohibited peptide hormone and related substance. Its use by athletes is banned under the relevant anti-doping code.
Confirmatory detection typically uses liquid chromatography with mass spectrometry. Immunoassays may be used for screening, but mass spectrometry provides structural confirmation.
No widely approved therapeutic indication exists for AOD-9604. It has been investigated in clinical studies, but regulatory approvals for general medical use are not established.
AOD-9604 is a synthetic peptide fragment of human growth hormone. It corresponds to the C-terminal region known as hGH 176-191 and is studied for metabolic effects. It is not an approved therapeutic drug.