What is TESAMORELIN + IPAMORELIN?
Tesamorelin + Ipamorelin is a blended preparation combining two structurally distinct synthetic peptides that are frequently studied together in the growth hormone secretagogue field. Tesamorelin (CAS 218949-48-5) is a 44-amino-acid analogue of growth hormone-releasing hormone (GHRH). Its sequence carries a trans-3-hexenoyl modification at the N-terminus, a lipophilic acyl group documented on its certificate of analysis that distinguishes it from unmodified GHRH. The molecule has the molecular formula C221H366N72O67S and a molecular weight of 5135.86, placing it among the larger synthetic peptides handled in this class of research material.
Ipamorelin (CAS 170851-70-4) is a considerably smaller pentapeptide with the sequence Aib-His-D-2-Nal-D-Phe-Lys-NH2, a molecular formula of C38H49N9O5, and a molecular weight of 711.85. Its structure incorporates non-proteinogenic and D-configured residues — aminoisobutyric acid (Aib), D-2-naphthylalanine, and D-phenylalanine — along with a C-terminal amide, structural features associated with the ghrelin/growth hormone secretagogue receptor (GHS-R) peptide family. This design contrasts with the GHRH-analogue architecture of Tesamorelin, and the two are classified separately: one as a releasing-hormone analogue, the other as a secretagogue pentapeptide.
Within a research context, both peptides are investigated in in-vitro and preclinical models of the somatotropic (growth hormone) axis and receptor signaling, and the blend format is of interest to laboratories examining how a GHRH-analogue and a GHS-R-active pentapeptide behave as a combined reference sample. This material is offered strictly for laboratory research use only. It is not a drug, supplement, or article intended for diagnostic, therapeutic, or human or veterinary use, and no physiological outcomes are described or implied.
Reconstitution & handling
The blend is supplied as a lyophilized (freeze-dried) powder and is typically reconstituted with bacteriostatic or sterile water for laboratory handling; other compatible aqueous solvents may be selected according to the experimental protocol. To dissolve the material, the chosen diluent should be directed slowly against the inner wall of the vial rather than injected forcefully onto the powder cake, allowing the solid to hydrate gently. The vial is then left to stand and swirled lightly until a clear, particulate-free solution forms; vigorous shaking or vortexing is generally avoided because mechanical shear and foaming can promote peptide aggregation and denaturation.
Both components are generally soluble in aqueous media, with the smaller amidated Ipamorelin pentapeptide dissolving readily and the larger acyl-modified Tesamorelin benefiting from unhurried, gentle handling. Reconstitution should be performed at the concentration required by the study design, and solutions handled aseptically. This information describes dissolution chemistry only and is not administration guidance.
Storage & stability
In lyophilized form, the peptide blend is best stored sealed and protected from light, moisture, and heat, typically frozen for long-term stability, where dry powder is generally the most stable state for material of this type. Once reconstituted, the solution should be kept refrigerated, protected from light, and used within a limited working window; freeze-thaw cycling is minimized because repeated temperature swings can degrade peptide integrity. Aliquoting the reconstituted solution into single-use fractions before freezing is a common laboratory practice to preserve sample quality across the study period.
How it's tested
Identity and purity of the blend are verified analytically before release. Reversed-phase high-performance liquid chromatography (HPLC) is used to quantify chromatographic purity, confirmed here at ≥99%, and to resolve each peptide from process-related impurities. Mass spectrometry (MS) confirms molecular identity by matching the observed masses against the expected values for each component — 5135.86 for Tesamorelin and 711.85 for Ipamorelin. Results are documented on a certificate of analysis (COA) available with the material, providing traceable confirmation of purity and identity for laboratory records.