The short version of mass spectrometry fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-02-12. Anything still debated is marked as such rather than presented as settled.
AOD-9604 is a synthetic peptide modeled on the C-terminal region of human growth hormone. It corresponds to residues 176-191 of the 191-amino-acid hGH sequence. The fragment is not the full hormone and lacks the receptor-binding region associated with growth and metabolic effects of hGH. Researchers developed it to isolate a specific portion of hGH for study. Its exact sequence and length are often stated in peptide catalogs and patents.
The peptide is frequently described as a growth hormone fragment, although it is chemically distinct from full-length hGH. AOD-9604 contains 16 amino acids and includes two cysteine residues that can form an intramolecular disulfide bond. In solution, this structural feature can influence folding, aggregation, and stability. Published descriptions sometimes call it hGH 176-191 or AOD9604, with spacing and capitalization varying. Such naming differences can complicate literature searches, database entries, and product verification.
Researchers have studied the fragment in cell and animal models to understand its metabolic actions. Some experiments report effects on fat breakdown and fat storage pathways, but the underlying mechanism remains incompletely defined. AOD-9604 does not appear to stimulate the same broad growth hormone receptor signaling as full-length hGH. Whether its observed activities arise from direct receptor interactions or downstream metabolic changes is an open question. Results from different assays are not always consistent.
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.
Research on AOD-9604 also examines how the peptide is measured in biological samples. Analytical methods may include liquid chromatography coupled with mass spectrometry, immunoassays, or both. Detection can be challenging because the peptide is small and may be present at low concentrations. Published methods vary in sensitivity and specificity, so comparative interpretation requires attention to validation details. The presence of related hGH fragments can complicate identification in some matrices.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic peptide | Derived from a fragment of human growth hormone |
| Sequence basis | hGH residues 176-191 | Commonly described as a 16-amino-acid fragment |
| Appearance | White to off-white powder | Typical for lyophilized research peptides |
| Solubility | Soluble in water or aqueous buffer | Exact solubility depends on pH and purity |
| Common synonyms | AOD9604; hGH 176-191 | Spelling and punctuation vary across sources |
AOD9604 is a synthetic peptide modeled on the C-terminal region of human growth hormone. It corresponds to a short sequence near the end of the 191-amino-acid hormone, often described as residues 176–191 or a related fragment. Researchers designed it to separate metabolic effects from the growth-promoting actions of full-length growth hormone. Early work in the 1990s explored it as a candidate for weight and lipid disorders. It is not a naturally circulating hormone fragment produced in large amounts.
Laboratory studies have reported that AOD9604 can increase lipolysis and reduce lipid accumulation in fat cells. The precise molecular target remains uncertain, and the compound does not appear to activate the growth hormone receptor in the same way as full-length hGH. Proposed mechanisms include effects on beta-adrenergic signaling and enzymes involved in fatty acid synthesis, but these pathways are not firmly established. Because most evidence comes from cell and animal models, whether the same effects occur in humans is an open question.
Clinical development of AOD9604 included trials in people with obesity, but the results did not lead to approval as a prescription medicine in major markets. Interest later shifted to research settings and to unapproved products marketed for body composition. Regulatory agencies have questioned whether the peptide qualifies as a dietary ingredient, and some have issued warnings about its presence in supplements. Long-term human safety data are limited, and questions about efficacy, dosing, and target populations remain unresolved.
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 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.
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.
Detection and characterization of AOD-9604 in research and anti-doping settings typically rely on mass spectrometry coupled with liquid chromatography. These methods can identify the peptide by its mass and fragmentation pattern. Immunoassays may also be used in some screening contexts, but they can cross-react with related peptides. Because the molecule is small and may be present at low concentrations, sample preparation and method validation are important. Confirmatory analysis usually requires comparison with a certified reference standard.
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.
=== Medical Student Training in Aging Research (MSTAR) === The University of Texas Medical Student Training in Aging Research (UT-MSTAR) is an NIH-funded T35 short-term research training program administered by the Barshop Institute and supported by the National Institute on Aging. Established in 2025, the program is directed by Elena Volpi, MD, PhD, FGSA, and represents a unique statewide collaboration among the four largest medical schools in The University of Texas System: UT Health San Antonio, UTHealth Houston, UT Medical Branch, and UT Southwestern Medical Center. The program was created to address the growing national need for physician-scientists with expertise in aging research and geriatric medicine by introducing medical students to aging research early in their professional training. UT-MSTAR provides approximately 20 first-year medical students each year with an intensive eight-week summer research experience under the mentorship of accomplished investigators conducting basic, translational, clinical, behavioral, and population-based aging research. Students are paired with faculty mentors whose research encompasses the biology of aging, geroscience, Alzheimer's disease and related dementias, cardiovascular disease, metabolic disorders, frailty, sarcopenia, health disparities, and other age-related conditions.
== External links == Shodex Worldwide and Asia general website Shodex North and Latin America website Shodex Europe, Middle East, Africa website Showa Denko Develops New Shodex™ Analytical Column Resonac Website about Shodex HPLC columns
=== Gold's deep-hot biosphere === In the 1970s, Thomas Gold proposed the theory that life first developed not on the surface of the Earth, but several kilometers below the surface. It is claimed that the discovery of microbial life below the surface of another body in our Solar System would lend significant credence to this theory.
=== Betting scandal === In early February 2023 UFC introduced rules that banned athletes, coaches, and their close family from betting on UFC events. after the call for a sports betting fraud investigation was made on a fight involving Darrick Minner a student of James Krause, who is a UFC coach and avid bettor, and Shayilan Nuerdanbieke at UFC Fight Night: Rodriguez vs. Lemos. The UFC was informed by sources that suspicious betting patterns had been observed on the fight.
Sources: en.wikipedia.org
It thus represents an advantage over whole pancreas transplantation, which is more technically demanding and poses a risk of, for example, pancreatitis leading to organ loss. Another advantage is that patients do not require general anesthesia. Islet transplantation for type 1 diabetes (as of 2008) requires potent immunosuppression to prevent host rejection of donor islets. The islets are transplanted into a portal vein, which is then implanted in the liver. There is a risk of portal venous branch thrombosis and the low value of islet survival a few minutes after transplantation, because the vascular density at this site is after the surgery several months lower than in endogenous islets. Thus, neovascularization is key to islet survival, that is supported, for example, by VEGF produced by islets and vascular endothelial cells. However, intraportal transplantation has some other shortcomings, and so other alternative sites that would provide better microenvironment for islets implantation are being examined. Islet transplant research also focuses on islet encapsulation, CNI-free (calcineurin-inhibitor) immunosuppression, biomarkers of islet damage or islet donor shortage. An alternative source of beta cells, such insulin-producing cells derived from adult stem cells or progenitor cells would contribute to overcoming the shortage of donor organs for transplantation. The field of regenerative medicine is rapidly evolving and offers great hope for the nearest future. However, type 1 diabetes is the result of the autoimmune destruction of beta cells in the pancreas.
The causes of common gynecomastia remain uncertain, but are thought to result from an imbalance between the actions of estrogen, which stimulates breast tissue growth, and androgens, which inhibit breast tissue growth. Breast prominence can result from enlargement of glandular breast tissue, chest adipose tissue (fat), and skin, and is typically a combination. As in females, estrogen stimulates the growth of breast tissue in males. In addition to directly stimulating breast tissue growth, estrogens indirectly decrease secretion of testosterone by suppressing luteinizing hormone secretion, resulting in decreased testicular secretion of testosterone.
The periodontal ligament, commonly abbreviated as the PDL, are a group of specialized connective tissue fibers that essentially attach a tooth to the alveolar bone within which they sit. It inserts into root cementum on one side and onto alveolar bone on the other.
Sources: en.wikipedia.org
In American butchery, the sirloin steak is a cut of beef from the sirloin, the subprimal posterior to the short loin where the T-bone, porterhouse, and strip steaks are cut. The sirloin is divided into several parts. The top sirloin is the most prized part and is sold under that name. The bottom sirloin, which is less tender and much larger, is typically sold simply as "sirloin steak". The bottom sirloin connects to the sirloin tip roast. Sirloin steak is defined differently in different countries.
==== Canada, United Kingdom, and Europe ==== In Canada, e-cigarettes had an estimated value of 140 million CAD in 2015. There are numerous e-cigarette retail shops in Canada. A 2014 audit of retailers in four Canadian cities found that 94% of grocery stores, convenience stores, and tobacconist shops which sold e-cigarettes sold nicotine-free varieties only, while all vape shops stocked at least one nicotine-containing product. By 2015, the e-cigarette market had only reached a twentieth of the size of the tobacco market in the UK. In the UK in 2015 the "most prominent brands of cigalikes" were owned by tobacco companies, however, with the exception of one model, all the tank types came from "non-tobacco industry companies". Yet some tobacco industry products, while using prefilled cartridges, resemble tank models. By 2023, 1 survey by the Local Data Company counted 3,573 specialist vape shops in the UK, and NIQ data cited in press reporting put value sales of vaping products in Britain at £897.4 million. Sky News similarly reported that more than 230 independent vape shops opened in 2023, citing the same Local Data Company survey. France's e-cigarette market was estimated by Groupe Xerfi to be €130 million in 2015. Additionally, France's e-liquid market was estimated at €265 million. In December 2015, there were 2,400 vape shops in France, 400 fewer than in March of the same year. Industry organization Fivape said the reduction was due to consolidation, not to reduced demand.
== Forms and nomenclature == There are two forms or enantiomers of aspartic acid. The name "aspartic acid" can refer to either enantiomer or a mixture of two. Of these two forms, only one, "L-aspartic acid", is directly incorporated into proteins. The biological roles of its counterpart, "D-aspartic acid" are more limited. Where enzymatic synthesis will produce one or the other, most chemical syntheses will produce both forms, "DL-aspartic acid", known as a racemic mixture.
Engines (includes all models from 1998 to 2003) 1.3 L B3-ME SOHC I4 1.5 L ZL-DE DOHC I4 1.5 L ZL-VE S-VT I4 1.6 L ZM-DE DOHC I4 1.8 L FP-DE DOHC I4 2.0 L FS, 130 hp (97 kW; 132 PS) / 135 lb⋅ft (183 N⋅m) 2.0 L FS-ZE (2001 Sport 20) 2.0 L RF Diesel
Sources: en.wikipedia.org
No, it is a synthetic peptide fragment corresponding to a small portion of hGH. It is not the full 191-amino-acid hormone and does not reproduce all of hGH's effects.
It is commonly described as a 16-amino-acid peptide based on residues 176-191 of human growth hormone. Some sources vary in notation, so checking the stated sequence is useful.
It is not typically described as a standalone natural hormone. The sequence is derived from the C-terminal region of human growth hormone, but the synthetic peptide is a laboratory-made construct.
No. It is not approved as a therapeutic drug by major regulators. It is sold for research purposes in many settings, which is not the same as clinical approval.