What AOD-9604 is
AOD-9604 is a synthetic peptide of 16 amino acids that reproduces the C-terminal region of human growth hormone, residues 176 to 191, with an additional tyrosine at the N-terminus. It was developed at Monash University in Melbourne in the 1990s by a group led by Frank Ng, who were mapping the C-terminal region of the growth hormone molecule.
The sequence retains the disulfide bridge between the two cysteines of the parent protein, corresponding to Cys182 and Cys189 of growth hormone, so the peptide is cyclic across most of its length. It carries no lipid or other modification beyond the added tyrosine. The average molecular weight is approximately 1,815 g/mol and the CAS number is 221231-10-3. The published literature on the compound, with references, is collected in the monograph.
What you receive
Each vial contains AOD-9604 as a white lyophilised powder, sealed with a flip-off cap over a crimped stopper, in the net quantity stated on the label: 5 mg. There is no carrier, mannitol or other excipient unless the batch certificate says otherwise. The batch number is printed on the label and matches the certificate in our register.
Reading the certificate for an AOD-9604 batch
Purity by reversed-phase HPLC is reported as the area of the main peak against all peaks and should be above 99% for a peptide of this length. Identity by LC-MS is reported as the observed mass against the expected mass of about 1,815 Da. The disulfide bridge matters here: the oxidised, bridged form is two daltons lighter than the reduced open-chain form, and a careful certificate will state which is expected and show that the observed mass matches. A batch in which a substantial fraction remains reduced, or in which two chains have paired through intermolecular disulfides to give a dimer at roughly twice the mass, has been handled poorly. Net peptide content gives the milligrams of peptide actually present after allowing for water and counter-ions.
Typical impurities are deletion sequences, a small amount of the reduced form, and a trace of dimer, all of which separate from the main peak on HPLC. At the sub-1% level these are normal. Our guide to reading a certificate of analysis shows annotated examples, and HPLC and LC-MS explained describes the methods.
Storage and handling
Sealed vials should be kept refrigerated at 2 to 8 °C and protected from light; −20 °C is preferable for storage beyond a few months, and the lyophilised powder is stable for well over a year under those conditions. Allow the vial to reach room temperature before opening to avoid condensation on the powder. The peptide dissolves in water or bacteriostatic water; solutions for in-vitro work should avoid thiol reagents such as dithiothreitol, which reduce the disulfide, unless the open form is wanted. Solutions should be prepared fresh or aliquoted and frozen; the storage and stability guide covers solvents, concentrations and aliquoting.