Research comparison
Two GHRH receptor agonists, two very different pharmacokinetic profiles. Sermorelin is the original 29-amino-acid GHRH analogue with a serum half-life of minutes. CJC 1295 with DAC is a modified analogue covalently bound to albumin, extending its half-life to approximately a week. Both are supplied for in-vitro laboratory research only.
| CJC 1295 (with DAC) | Sermorelin | |
|---|---|---|
| Receptor profile | GHRH receptor agonist (extended via albumin binding) | GHRH receptor agonist (native fragment) |
| Residue count | 30 amino acids + DAC | 29 amino acids |
| Molecular weight | ~3,367.9 g/mol | ~3,357.9 g/mol |
| Reported half-life | ~6–8 days (albumin-bound) | ~10–20 minutes |
| Backbone modifications | D-Ala², Gln⁸, Ala¹⁵, Leu²⁷ + Lys³⁰(MPA) | Native GHRH(1-29) |
| CAS Number | 863288-34-0 | 86168-78-7 |
| Reference page | CJC 1295 (DAC) → | Sermorelin → |
Sermorelin is a synthetic 29-amino-acid peptide corresponding to the first 29 residues of native human growth-hormone-releasing hormone (GHRH). It is the shortest fully-active fragment of native GHRH and is used widely in published literature as the reference compound for GHRH receptor pharmacology.
The peptide retains the native sequence (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-NH2) without modifications, which means it is rapidly cleared from circulation by enzymes such as dipeptidyl peptidase-4 (DPP-4). The reported serum half-life is 10–20 minutes in published pharmacokinetic studies. This short window makes Sermorelin valuable for studies that aim to mimic native pulsatile GHRH signalling.
CJC 1295 with DAC begins with a modified GHRH backbone - the same 1-29 sequence as Sermorelin but with four substitutions designed to resist enzymatic degradation: D-Ala² (resists DPP-4), Gln⁸, Ala¹⁵ and Leu²⁷. A 30th residue (Lys) is appended at the C-terminus and conjugated to maleimidopropionic acid (MPA) - the Drug Affinity Complex.
Once injected, the maleimide group reacts with the free cysteine-34 thiol of serum albumin, forming a stable covalent bond. This effectively chains the GHRH analogue to albumin's natural ~19-day circulation time, producing a reported serum half-life of approximately 6–8 days. This extended pulse-area-under-curve (AUC) profile is the defining feature of CJC 1295 with DAC and the reason it is studied for prolonged GH-axis research applications.
| Property | CJC 1295 (DAC) | Sermorelin |
|---|---|---|
| GHRH receptor | Agonist (similar EC50) | Agonist (reference) |
| DPP-4 resistance | Yes (D-Ala²) | No (rapid cleavage) |
| Albumin binding | Covalent, via Lys³⁰(MPA) | None |
| Half-life | ~6–8 days | ~10–20 minutes |
| Pulse pattern in vivo | Sustained / continuous | Pulsatile / brief |
| Storage (reconstituted) | Up to 30 days at 2–8 °C | ~14 days at 2–8 °C |
Both peptides are supplied as lyophilised powder in sealed glass vials. Reconstitute with bacteriostatic water added slowly down the side wall, swirling gently until fully dissolved. Use the on-site Reconstitution Volume Calculator for mg/mL maths.
| Compound | Lyophilised storage | Reconstituted shelf life |
|---|---|---|
| CJC 1295 (DAC) | 2–8 °C, 24+ months | ~30 days at 2–8 °C |
| Sermorelin | 2–8 °C, 24+ months | ~14 days at 2–8 °C |
Both compounds are independently HPLC-verified by Janoshik Analytical at 99%+ purity. Where a Janoshik report has been issued for the current batch it is supplied with the order; otherwise we publish the verification record on the Purity page.
Both are synthetic GHRH receptor agonists, but they differ dramatically in serum half-life. Sermorelin is a 29-amino-acid analogue of native GHRH(1-29) with a reported half-life of 10–20 minutes. CJC 1295 with DAC includes a maleimide group that covalently binds serum albumin, extending the reported half-life to ~6–8 days.
The DAC (Drug Affinity Complex) is a maleimidopropionic acid moiety on Lys-30. After injection it reacts with serum albumin's free cysteine-34, forming a stable covalent bond. This piggybacks the peptide onto albumin's ~19-day half-life.
Sermorelin is the more widely cited reference for GHRH(1-29) receptor pharmacology in-vitro, since its sequence is the native bioactive fragment. CJC 1295 (DAC) is preferred in studies on long-acting analogues or albumin-binding pharmacokinetics.
No. CJC 1295 without DAC (Modified GRF 1-29) shares the modified backbone (D-Ala², Gln⁸, Ala¹⁵, Leu²⁷) but lacks the albumin-binding maleimide. Half-life is ~30 minutes - longer than Sermorelin but much shorter than the DAC version.
Yes. Both remain stable lyophilised at 2–8 °C for 24+ months. Reconstituted Sermorelin uses within 14 days; CJC 1295 (DAC) within 30 days. Refrigerate and avoid prolonged room-temperature exposure.