A practical reference on mass spectrometry: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-05-31 and is reviewed periodically as new material appears.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Lyophilized form; may appear as cake |
| Solubility class | Water-soluble | Often reconstituted in aqueous buffer |
| Typical storage temperature | −20 °C or below | Protect from light and moisture |
| Typical analytical method | RP-HPLC and mass spectrometry | Used for purity and identity |
| Common synonyms | AOD-9604; AOD9604; hGH fragment 176-191 | Research name and fragment description |
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.
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.
Interest in AOD-9604 arose from attempts to separate metabolic effects from growth effects attributed to hGH. Early work explored whether the fragment could influence lipolysis or fat oxidation without promoting growth. Those questions remain partly unresolved because human data are limited and results have varied across studies. The peptide is not a hormone replacement for hGH and is not equivalent to hGH in clinical use. Its research history includes both laboratory studies and commercial marketing claims that are not the same as regulatory approval.
AOD-9604 is a synthetic peptide whose structure corresponds to a C-terminal segment of human growth hormone. It is often described as hGH fragment 176-191, a 16-amino-acid sequence. The peptide was designed to isolate a region of hGH associated with fat metabolism while avoiding the full hormone's growth-promoting actions. Laboratory and commercial materials typically present it as a lyophilized powder for research use. Its identity is defined by amino acid sequence, not by a single brand.
== Technology == Vaxess's business plan is based around a technology developed by Tufts University Professors Fiorenzo Omenetto and David Kaplan. The technology uses a silk-derived protein called fibroin to stabilize vaccines so that they can be shipped and stored without refrigeration, eliminating the need for the cold chain. Vaxess is working with vaccine manufacturers to develop heat-stable vaccines and targeting a product launch by 2019.
=== Elution-extrusion === The extrusion of stationary phase from the column at the end of a separation experiment by stopping rotation and pumping solvent or gas through the column was used by CCC practitioners before the term EECCC was suggested. In elution-extrusion mode (EECCC), The mobile phase is extruded after a certain point by switching the phase being pumped into the system whilst maintaining rotation. For example, if the separation has been initiated with the aqueous phase as the mobile phase at a certain point the organic phase is pumped through the column which effectively pushes out both phases that are present in the column at the time of switching. The complete sample is eluted in the order of polarity (either normal or reversed) without loss of resolution by diffusion. It requires only one column volume of solvent phase and leaves the column full of fresh stationary phase for the subsequent separation.
== Enteral formulations == Oral drugs are commonly taken as tablets or capsules. The drug (active substance) itself needs to be soluble in aqueous solution at a controlled rate. Such factors as particle size and crystal form can significantly affect dissolution. Fast dissolution is not always ideal. For example, slow dissolution rates can prolong the duration of action or avoid initial high plasma levels. Treatment of active ingredient by special ways such as spherical crystallization can have some advantages for drug formulation.
Automation: high throughput screening, LIMS, robotics. Protein/Peptide Chemistry: amino acid analysis, N- and C-terminal sequencing, peptide synthesis, peptide/protein arrays. Biophysics: calorimetry, CD, fluorescence, light scattering, SPR, ultracentrifugation. Flow Cytometry Fluorescence Activating Cell Sorting Protein Expression, Identification, and Profiling: differential fluorescence, conventional 2-D gel electrophoresis, disease biomarker discovery. Gene Expression and Profiling: gene arrays, real-time PCR. Mass Spectrometry: qualitative, quantitative, and structural analysis of proteins, carbohydrates, oligonucleotides, and lipids. Microscopy light microscopy and imaging, Confocal Microscopy Nucleic Acid Chemistry: DNA sequencing, DNA synthesis, RNA synthesis, genotyping. Separations: 1- and 2-D PAGE, capillary electrophoresis, chromatography. Quality Control: GLP, GMP, quality and compliance. Universal Proteomics Standard (UPS), a mixture of proteins used as reference standard in proteomics, introduced by the above-mentioned sPRG. This includes two sets: the original (UPS1, where all 48 proteins are at 48 pmol), and a dynamic range of concentrations (called UPS2), ranging from 500 amol to 50 pmol. Other: bioinformatics, carbohydrate analysis, differential display, recombinant protein production.
Sources: en.wikipedia.org
== History == Efficacy was evaluated in CADENZA (NCT03386513), a multi-center, open-label, single-arm clinical trial that included adult participants with treatment-naïve blastic plasmacytoid dendritic cell neoplasm (N=33) or relapsed or refractory blastic plasmacytoid dendritic cell neoplasm (N=51), without evidence of active central nervous system disease. Efficacy was based on the rate of complete remission or clinical complete remission. The trial included 116 adult participants with CD123-positive blood or bone marrow cancers, of whom 84 participants had blastic plasmacytoid dendritic cell neoplasm. There were 33 participants who had blastic plasmacytoid dendritic cell neoplasm that was never treated before, and 51 participants had blastic plasmacytoid dendritic cell neoplasm that either came back after previous treatment or did not get better with other treatment(s). The trial occurred at 18 locations in four countries: the United States, Italy, Spain, and France. The study included 73 participants in the United States. The benefits and side effects of pivekimab sunirine were evaluated in one open-label trial in adult participants with CD123-positive blood or bone marrow cancers. The efficacy of pivekimab sunirine was evaluated in 84 participants with blastic plasmacytoid dendritic cell neoplasm who received pivekimab sunirine intravenously (through a vein) once every three weeks until the disease worsened or participants experienced unacceptable side effects.
Catalase is used in the food industry for removing hydrogen peroxide from milk prior to cheese production. Another use is in food wrappers, where it prevents food from oxidizing. Catalase is also used in the textile industry, removing hydrogen peroxide from fabrics to make sure the material is peroxide-free. A minor use is in contact lens hygiene – a few lens-cleaning products disinfect the lens using a hydrogen peroxide solution; a solution containing catalase is then used to decompose the hydrogen peroxide before the lens is used again.
The advent of global decolonisation and the subsequent rise in prominence of the Soviet Union among several newly independent African states was viewed with wariness by the South African government. National Party politicians began warning it would be only a matter of time before they were faced with a Soviet-directed insurgency on their borders. Outlying regions in South West Africa, namely the Caprivi Strip, became the focus of massive SADF air and ground training manoeuvres, as well as heightened border patrols. A year before SWAPO made the decision to send its first SWALA recruits abroad for guerrilla training, South Africa established fortified police outposts along the Caprivi Strip for the express purpose of deterring insurgents. When SWALA cadres armed with Soviet weapons and training began to make their appearance in South West Africa, the National Party believed its fears of a local Soviet proxy force had finally been realised. The Soviet Union took a keen interest in Africa's independence movements and initially hoped that the cultivation of socialist client states on the continent would deny their economic and strategic resources to the West. Soviet training of SWALA was thus not confined to tactical matters but extended to Marxist–Leninist political theory, and the procedures for establishing an effective political-military infrastructure. In addition to training, the Soviets quickly became SWALA's leading supplier of arms and money.
Building trust and acceptance of a licensed vaccine among the public is a task of communication by governments and healthcare personnel to ensure a vaccination campaign proceeds smoothly, saves lives, and enables economic recovery. When a vaccine is licensed, it will initially be in limited supply due to variable manufacturing, distribution, and logistical factors, requiring an allocation plan for the limited supply and which population segments should be prioritized to first receive the vaccine.
==== United States Food and Drug Administration ==== In the United States of America, which was otherwise unaffected by the scares, the US distributor of White Rabbit candies recalled the product when samples found in Hartford showed traces of melamine. The candy's maker and subsidiary of Bright Foods, Guan Sheng Yuan, issued a recall to the 50 countries to which it exported. The U.S. Food and Drug Administration said while food containing melamine below 2.5 parts per million generally did not raise concerns, its scientists were "currently unable to establish any level of melamine and melamine-related compounds in infant formula that does not raise public health concerns". On 12 November 2008, the FDA issued a general alert against all finished food products from China, saying that information received from government sources in a number of countries indicates a wide range and variety of products from a variety of producers have been manufactured using melamine-contaminated milk was a recurring problem. In late November, after the FDA found traces of melamine in one Nestle and one Mead Johnson infant product, the FDA concluded melamine or cyanuric acid alone, "at or below 1 part per million in infant formula do not raise public health concerns" in babies. The United States Food and Drug Administration opened its first overseas inspection offices in November 2008, with bureaus in Shanghai, Beijing and Guangzhou.
Sources: en.wikipedia.org
Lyophilized powder is commonly stored at −20 °C or below, protected from light and moisture. Reconstituted solutions are typically kept refrigerated and used within a limited period.
Reversed-phase HPLC and mass spectrometry are standard checks. They confirm peptide purity and molecular mass, but they do not by themselves demonstrate biological activity.
Synthesis, purification, and handling conditions can differ, leading to variations in purity and salt content. Certificates of analysis help, but independent testing is often needed for verification.
No. Major drug regulators have not approved AOD-9604 for weight loss or any other therapeutic indication. It remains an investigational compound studied in research settings.