Tesamorelin: Research Compound Profile

This reference page summarizes the published chemical identity of Tesamorelin as a laboratory research material. It covers registry identifiers, molecular structure, physical appearance, and the analytical methods used to confirm identity and purity. It makes no claims about biological activity and is intended only as a factual chemistry reference for researchers cataloguing the compound.

Compound identity

Tesamorelin is a synthetic analog of human GRF (GRF, also written GHRH). It is registered under CAS number 218949-48-5 and catalogued in PubChem as CID 16137828. Structurally it reproduces the 44-residue GRF(1-44) amino-acid sequence with a stabilizing modification at the amino terminus, which distinguishes it from the unmodified parent peptide. In laboratory records it is commonly filed under the GRF-analog class of research peptides.

Molecular structure and properties

The reported molecular formula is C₂₂₁H₃₆₆N₇₂O₆₇S, corresponding to an average molecular weight of approximately 5135.9 Da. The single sulfur atom reflects one methionine residue within the chain. The defining structural feature is a trans-3-hexenoyl group attached to the N-terminal tyrosine residue, a modification that increases the chemical stability of the molecule relative to native GRF.

The full published sequence is: (trans-3-hexenoyl)-Tyr-Ala-Asp-Ala-Ile-Phe-Thr-Asn-Ser-Tyr-Arg-Lys-Val-Leu-Gly-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Met-Ser-Arg-Gln-Gln-Gly-Glu-Ser-Asn-Gln-Glu-Arg-Gly-Ala-Arg-Ala-Arg-Leu-NH₂. The C-terminus is amidated, and the chain contains several Gly, Arg, and Leu residues typical of the GRF family. These values are verifiable on PubChem and standard chemical registries and should be checked against the batch-specific certificate before a compound is entered into any catalogue.

Appearance and physical form

Research-grade Tesamorelin is typically supplied as a lyophilized (freeze-dried) white to off-white powder or cake sealed in a vial. In this dried state it is comparatively stable for storage. For laboratory handling it dissolves in sterile water to give a clear, colourless solution. As with most long-chain peptides, repeated freezing and thawing of a prepared solution is generally avoided in favour of small working aliquots, and cold storage is standard practice.

Identity and purity testing

Because peptides of this length can carry sequence-related and process-related impurities, identity and purity are confirmed by orthogonal analytical methods rather than a single test:

• LC-MS (liquid chromatography-mass spectrometry): separates the sample and measures the mass-to-charge ratio of the eluting species, allowing the observed molecular mass to be matched against the theoretical value calculated from the formula above.
• HRMS (high-resolution mass spectrometry): resolves masses to several decimal places, giving a tighter confirmation of the molecular formula and helping distinguish the target from closely related impurities.
• HPLC (high-performance liquid chromatography): quantifies chromatographic purity as a percentage of total peak area; the separation performance of the column determines how well minor related peaks are resolved from the main peak.

Together these methods answer two separate questions: is the material the correct molecule (identity), and how much of the sample is that molecule (purity).

How to read a Certificate of Analysis

A Certificate of Analysis (COA) documents the analytical results for one specific batch. When reviewing a Tesamorelin COA, researchers typically check that the batch or lot number matches the vial, that the identity method (LC-MS or HRMS) reports an observed mass consistent with ~5135.9 Da, that the stated purity figure names its method (for example HPLC area percent), and that the certificate names the laboratory and date. A purity figure with no method attached carries little meaning. Further guidance on interpreting these documents is collected in our COA library.

Batch testing at livvmore

Every livvmore research batch is identity- and purity-tested at the USC Alfred E. Mann Multi-Omics Mass Spectrometry Core, a university laboratory, using LC-MS and HRMS. For Tesamorelin, batch B40001 was documented at 99.2% by the Core, and the corresponding certificate is published rather than held on request. Details of the testing programme are described on our quality and testing page.

Research context

Tesamorelin has been described in the published literature as a stabilized GRF(1-44) analog, and its structure and registry data are indexed in public chemistry resources including PubChem (CID 16137828). Researchers cataloguing the compound should study the batch COA, not a general reference, as the authoritative record of what a given vial contains, since molecular mass and purity are properties of the specific lot rather than of the name alone.

For laboratory research use only. Not for human or veterinary use.

Frequently asked questions

What is the CAS number and molecular weight of Tesamorelin?

Tesamorelin is registered under CAS number 218949-48-5. Its molecular formula is C221H366N72O67S, giving an average molecular weight of approximately 5135.9 Da. It is indexed in PubChem as CID 16137828.

How many amino acids does Tesamorelin contain?

Tesamorelin is a 44-residue analog of human GRF (GRF/GHRH). It reproduces the GRF(1-44) sequence and adds a trans-3-hexenoyl group on the N-terminal tyrosine residue, with an amidated C-terminus.

What does research-grade Tesamorelin look like?

It is typically supplied as a lyophilized white to off-white powder or cake in a sealed vial. For laboratory handling it dissolves in sterile water to form a clear, colourless solution.

How is the identity and purity of Tesamorelin confirmed?

Identity is confirmed by mass spectrometry (LC-MS and HRMS), which matches the observed molecular mass against the theoretical ~5135.9 Da. Purity is measured by HPLC as a percentage of total peak area. Using these orthogonal methods separates the questions of what the molecule is from how much of it is present.

What purity is documented for the livvmore Tesamorelin batch?

livvmore batch B40001 of Tesamorelin was documented at the estimated purity recorded on its Certificate of Analysis by the USC Alfred E. Mann Multi-Omics Mass Spectrometry Core, a university laboratory, using LC-MS/HRMS. The certificate is published rather than provided only on request.