Pure North Peptides Journal · Compendium
Sermorelin: GHRH 1–29 reference standard for growth-axis research
Published 2024-04-25 · Pure North Peptides Editorial · Canada
Short answer. Sermorelin is GHRH 1–29, the N-terminal active fragment of human growth-hormone-releasing hormone, supplied lyophilized as a research reference standard.
Sequence
The 29-residue active fragment retains full GHRH-receptor agonism in receptor-binding assays. The C-terminal truncation (residues 30–44 of native GHRH) is dispensable for receptor activation, although it contributes to plasma stability — Sermorelin's in-vivo half-life is shorter than full-length GHRH 1–44.
Why use Sermorelin instead of full GHRH
- Synthesis cost: shorter peptide = cleaner SPPS, fewer truncation artifacts, lower per-mg cost.
- Receptor specificity: 1–29 retains the affinity-determining residues without the additional C-terminal sequence that can interact with off-target proteases.
- Reference comparability: Sermorelin is the standard "minimal-active-GHRH" comparator in published receptor-binding screens.
Reference standard criteria
- RP-HPLC purity ≥ 99% at 220 nm.
- ESI-MS at theoretical mass 3357.93 Da ± 0.5 Da.
- Net peptide content ≥ 80% by AAA.
- Residual TFA < 1.0%.
Reconstitution
Sermorelin reconstitutes cleanly in bacteriostatic water at concentrations up to 5 mg/mL. Use 1.0–2.0 mL water for a 5 mg vial. The lyophilized cake dissolves in 30–60 seconds with gentle swirling. Reconstituted solution is stable 28 days at 2–8 °C.
Comparison neighbors
For research on stabilized GHRH analogs, see our CJC-1295 DAC vs non-DAC piece and the Tesamorelin guide. The three-peptide set — Sermorelin (1–29), CJC-1295 (1–29 + lipidation), Tesamorelin (1–44 + N-terminal modification) — covers the GHRH-analog stability spectrum.
Sermorelin is not currently in the Pure North Peptides catalog. Email purenorthpeptides@proton.me if you would like to be notified if it is added in the future, or browse the current catalog →
Frequently asked questions
What is Sermorelin?
Sermorelin is the 29-amino-acid N-terminal active fragment of human GHRH (growth-hormone-releasing hormone), supplied as a research reference standard.
How does Sermorelin compare to CJC-1295?
Sermorelin is the unmodified GHRH 1–29; CJC-1295 adds a lipidation that extends in-vivo half-life. In-vitro affinity at GHRH-R is similar.
What is Sermorelin's molecular weight?
Theoretical mass 3357.93 Da, confirmed by ESI-MS within 0.5 Da on a competent COA.
How is Sermorelin stored?
Lyophilized, desiccated. After reconstitution, 2–8 °C for 28 days or −80 °C aliquots for longer.
Where to source Sermorelin in Canada?
Sermorelin is not currently stocked in the Pure North Peptides catalog. Email purenorthpeptides@proton.me to ask about future availability.
Disclaimer: All Pure North Peptides products are supplied for laboratory research use only. They are not approved by Health Canada as drugs. See our research-use declaration for full terms.