CJC-1295 vs sermorelin: a research-compound comparison
Researchers comparing CJC-1295 and sermorelin are usually weighing two GHRH-analogue research peptides that differ mainly in stability and duration of action. This page compares them on structure, molecular properties, and GHRH-receptor mechanism context only. Both are supplied strictly as chemical reference materials for in-vitro laboratory research and are not approved for human or veterinary use.
CJC-1295 vs sermorelin at a glance
| Property | CJC-1295 | Sermorelin |
|---|---|---|
| Peptide class | Modified GHRH(1-29) analogue | GHRH(1-29) fragment |
| Molecular weight | 3367.97 g/mol (no-DAC); 3647.30 g/mol (with-DAC) | 3357.93 g/mol |
| Molecular formula | C₁₅₂H₂₅₂N₄₄O₄₂ (no-DAC); C₁₆₅H₂₆₉N₄₇O₄₆ (with-DAC) | C₁₄₉H₂₄₆N₄₄O₄₂S |
| CAS number | 863288-34-0 (no-DAC); 446262-90-4 (with-DAC) | 86168-78-7 |
| Receptor (research) | GHRH receptor (class B GPCR) | GHRH receptor (class B GPCR) |
| Key modification | Stabilising substitutions vs native GHRH(1-29); optional DAC (MPA-Lys30) for albumin binding and extended half-life | None — native 1-29 sequence |
| Relative duration (research models) | Long-acting, especially the with-DAC variant | Short-acting |
| Contains sulfur | No (both no-DAC and with-DAC forms) | Yes (methionine) |
Sermorelin in research
Sermorelin corresponds to GHRH(1-29), the N-terminal active fragment of native growth-hormone-releasing hormone and the shortest fully active GHRH sequence. In research models it binds the GHRH receptor — a class B G-protein-coupled receptor on anterior-pituitary somatotrophs — and is studied as a benchmark GHRH-analogue reference compound. It is a 29-residue peptide (about 3357.93 g/mol, C₁₄₉H₂₄₆N₄₄O₄₂S, CAS 86168-78-7) with a comparatively short research half-life, and it is the only one of the two that contains a sulfur atom (a methionine residue). Supplied for in-vitro research only.
CJC-1295 in research
CJC-1295 is a modified GHRH(1-29) analogue carrying amino-acid substitutions that increase resistance to enzymatic degradation relative to the native sequence. The base no-DAC form, also catalogued as Modified GRF 1-29, is about 3367.97 g/mol (C₁₅₂H₂₅₂N₄₄O₄₂, CAS 863288-34-0). The with-DAC variant adds a Drug Affinity Complex group (a maleimidopropionyl-lysine, MPA-Lys30, modification, CAS 446262-90-4, about 3647.30 g/mol, C₁₆₅H₂₆₉N₄₇O₄₆) that binds albumin and markedly extends the duration of GHRH-receptor stimulation in research models; Teichman et al. (2006) characterised CJC-1295 as a long-acting GHRH analogue with prolonged GH and IGF-I stimulation. The two forms differ explicitly in formula, molecular weight, and duration. Supplied for in-vitro research only — no human-use, dosing, or therapeutic claims are made.
How CJC-1295 and sermorelin differ
- Sequence modification: CJC-1295 carries stabilising substitutions on the GHRH(1-29) backbone, whereas sermorelin is the native, unmodified 1-29 fragment.
- Size: the CJC-1295 no-DAC form (about 3367.97 g/mol) and with-DAC form (about 3647.30 g/mol) versus sermorelin at about 3357.93 g/mol.
- Duration in research models: CJC-1295, and especially its with-DAC variant, is long-acting, while sermorelin is short-acting.
- Catalog distinction: CJC-1295 is offered in both with-DAC and without-DAC forms, which differ in formula, molecular weight, and research half-life.
- Composition: only sermorelin contains a sulfur atom (methionine); neither CJC-1295 form does.
Why researchers compare them
Because CJC-1295 and sermorelin target the same GHRH receptor but have different stability profiles, they are studied as a short-acting versus long-acting GHRH-analogue pair rather than as substitutes. Nexus stocks sermorelin alongside both CJC-1295 forms — with-DAC and without-DAC — so laboratories can run side-by-side reconstitution and identity work across the duration spectrum. As always, the individual per-compound Certificate of Analysis remains the source of truth for the identity and purity of each material. This comparison is strictly structural and mechanistic; no GH-elevation, anti-aging, or human-use claims are made.
Verification and certificates of analysis
All three compounds in the Nexus catalog are independently verified, with public Certificates of Analysis reporting HPLC area-percent purity and mass-spectrometry identity for the release batch. New to reading these records? Start with the guide to reading a peptide certificate of analysis, then review the full lab-verified archive.
Research FAQ
Are CJC-1295 and sermorelin the same thing?
No. Sermorelin is the native GHRH(1-29) fragment (about 3357.93 g/mol); CJC-1295 is a modified GHRH(1-29) analogue offered in a no-DAC form (about 3367.97 g/mol) and a longer-acting with-DAC form (about 3647.30 g/mol). They act on the same GHRH receptor but have different structures and stability profiles.
What is the difference between CJC-1295 with DAC and without DAC?
The with-DAC variant adds a Drug Affinity Complex group (a maleimidopropionyl-lysine, MPA-Lys30, modification) that binds albumin and extends the duration of GHRH-receptor stimulation in research models. The two forms differ in molecular formula, molecular weight (about 3647.30 vs 3367.97 g/mol), and research half-life.
What is the molecular weight of CJC-1295 vs sermorelin?
Sermorelin is about 3357.93 g/mol (C₁₄₉H₂₄₆N₄₄O₄₂S). CJC-1295 is about 3367.97 g/mol in its no-DAC form (C₁₅₂H₂₅₂N₄₄O₄₂) and about 3647.30 g/mol in its with-DAC form (C₁₆₅H₂₆₉N₄₇O₄₆).
Are CJC-1295 or sermorelin approved for human use?
No. Both are supplied strictly as chemical reference materials for in-vitro laboratory research. They are not approved for human consumption, veterinary use, or any therapeutic application.