AOD-9604 is a synthetic peptide corresponding to the C-terminal region of human growth hormone (hGH), spanning approximately residues 177-191, with an added N-terminal tyrosine that distinguishes the analog from the strictly native fragment. In research settings it is treated as a chemically defined tool compound whose identity rests entirely on that short, specified sequence and its single point of modification.
The parent sequence
The 15-residue core reproduces the portion of growth hormone associated with the lipid-metabolism signaling discussed in its mechanism of action. Because it represents only the C-terminal segment, it deliberately omits the residues responsible for growth hormone's receptor-activating region, making it a fragment rather than a functional hormone mimic.
The added tyrosine
Appending an N-terminal tyrosine (Tyr) is the defining engineering choice. The aromatic residue changes the molecule's physicochemical fingerprint, provides a convenient UV-absorbing handle for detection, and gives the fragment a distinct analytical signature relative to the unmodified hGH(177-191) sequence. How single-residue choices like this reshape a peptide's identity is outlined in understanding amino acid sequences.
Solid-phase synthesis
At only fifteen residues, AOD-9604 is well suited to standard Fmoc solid-phase peptide synthesis. The chain is assembled stepwise on a resin support, one protected amino acid at a time, then cleaved and deprotected. Short sequences like this are generally accessible to conventional synthesizers without the recombinant expression required for larger proteins.
Purification and lyophilization
Crude synthetic material contains truncated and deletion sequences that must be removed. Preparative reversed-phase chromatography isolates the target peptide, which is then converted to a stable dry powder by freeze-drying — the process described in what is lyophilization. Lyophilized material is easier to weigh, ship, and store than a solution.
Identity and purity verification
Analytical HPLC purity quantifies how much of the sample is the intended peptide, while mass spectrometry confirms the molecular weight matches the expected sequence including the extra tyrosine. Reviewing these figures on a certificate of analysis is covered in how to read a COA. For broader context on the compound, see the AOD-9604 research overview.
Sequence-dependent stability
As with any short linear peptide, chemical stability depends on sequence, terminal chemistry, residual moisture, and the surrounding matrix. Oxidation, deamidation, and peptide-bond hydrolysis are general degradation routes considered during analytical method development, although their relative importance must be established experimentally for each preparation. Stability studies therefore compare chromatographic profiles over time rather than assuming that a lyophilized appearance guarantees intact material. Reference standards, protected storage, and repeat mass measurements help distinguish true degradation products from synthesis-related impurities. These controls are especially important when small sequence variants could otherwise be mistaken for the intended C-terminal growth-hormone fragment.
Product page: AOD-9604 research vials.
Research Use Only. Supplied strictly for laboratory research and development — not for human or veterinary use, consumption, or any therapeutic or diagnostic purpose. This article is research education, not usage guidance.