Ipamorelin: structure and analysis

What is Ipamorelin?

Ipamorelin is a synthetic pentapeptide of the growth hormone secretagogue class. Unlike the GHRH analogs it is often grouped with, it is not derived from growth hormone-releasing hormone and shares no sequence with it — the grouping is functional class, not chemical lineage.

The sequence includes 2-aminoisobutyric acid, a non-natural amino acid not found in proteins. Its presence is a deliberate design feature: the additional methyl group constrains the local backbone conformation and removes a site available for enzymatic cleavage.

How is Ipamorelin produced?

Assembled by solid-phase peptide synthesis: the chain is built one residue at a time on an insoluble resin support, then cleaved from the resin, deprotected and purified — most commonly by reversed-phase high-performance liquid chromatography. The purified material is lyophilized to a dry solid.

The impurity profile that appears on a certificate is a record of where that process was imperfect: deletion sequences from an incomplete coupling, truncated chains, and species retaining a protecting group.

What are the molecular figures for Ipamorelin?

Calculated from the formula C38H49N9O5, not measured. The average molecular weight counts the natural abundance of each element's isotopes; the monoisotopic mass is the mass of the single most abundant isotopic composition, which is the figure a mass spectrometer is usually compared against.

The expected ions follow from the monoisotopic mass by adding one proton per charge. They are a starting point for recognising a spectrum, not a substitute for one: adducts, salts, modifications and multiply charged species all move the observed m/z, and the certificate reports what was actually measured for a batch.

Adducts, salts, modifications and multiply charged species all move an observed m/z away from any figure calculated here, and a certificate reports what was measured for a batch rather than what was expected of it.

What is the sequence of Ipamorelin?

No one-letter amino-acid sequence is published for Ipamorelin on this page. Ipamorelin carries 2-aminoisobutyric acid, a non-natural residue with no one-letter code, so a one-letter sequence would have to omit or approximate the residue that most distinguishes the molecule.

What establishes the material in a specific vial is the identity method and result stated on that batch's certificate, not a notation on a reference page.

How does Ipamorelin compare with related compounds?

Related compounds are not interchangeable. Published figures differ between them, and in this catalogue three compounds share a GHRH backbone while several share the same structural class — which is exactly why identity is confirmed analytically rather than inferred from the label.

How is the identity of Ipamorelin confirmed?

Mass spectrometry confirms the five-residue chain including the non-natural residue. Because 2-aminoisobutyric acid is not a standard amino acid, its incorporation is itself part of the identity confirmation — a species in which a standard residue was incorporated instead has a different mass.

At five residues the mass is low enough that a high-resolution measurement is a tight constraint on composition.

Which impurities can appear in Ipamorelin?

Non-natural residues change what a synthesis can get wrong. Coupling a sterically hindered amino acid such as 2-aminoisobutyric acid is less efficient than coupling a standard residue, so a deletion at that specific position is the most plausible sequence-related impurity.

As a short peptide it is chromatographically straightforward compared with the 29- and 44-residue GHRH analogs, where deletion products are numerous and closely spaced.

What does a certificate of analysis for Ipamorelin report?

A certificate for a batch of this material names the batch, names the issuing laboratory, and states for each parameter both the method used and the specification the result was measured against. Identity and purity are the two core results; net peptide content states how much of the fill weight is actually peptide.

A certificate belongs to a batch, not to a product line. When a new batch is released it is tested again, and the certificate published against it is that batch's certificate — a previous batch's result is never carried forward.

Is Ipamorelin for human use?

No. This page describes structure and analysis. It makes no claim about what this compound does, and none should be inferred from it. Material is supplied for laboratory research use only: it is not a drug, food, dietary supplement, cosmetic or medical device, it is not for human or veterinary consumption, and no dosing, administration or reconstitution guidance is provided for any such use.

References

• Ipamorelin — PubChem, National Library of Medicine
• Ipamorelin — ChEBI, European Bioinformatics Institute
• Ipamorelin — ChEMBL, European Bioinformatics Institute