CJC-1295 (No DAC) Research Guide: Modified GRF (1-29) Mechanism
CJC-1295 without DAC — also called Modified GRF (1-29) — is a short-acting GHRH analog used in pulsatile GH-release research protocols.
What is CJC-1295 without DAC?
CJC-1295 without DAC (Modified GRF 1-29, sometimes abbreviated ModGRF) is a synthetic peptide corresponding to the first 29 amino acids of endogenous growth hormone releasing hormone (GHRH), with four amino acid substitutions engineered to resist enzymatic degradation.
It is one of the most-studied GHRH analogs in preclinical growth-hormone release research and is frequently paired with a GHRP (such as Ipamorelin) to produce synergistic GH pulses.
Mechanism of action
CJC-1295 binds the GHRH receptor on somatotroph cells of the anterior pituitary, driving cAMP-mediated release of endogenous growth hormone. Because the peptide is cleared within roughly 30 minutes, GH output returns to baseline before the next physiologic pulse — preserving the natural pulsatility of the GH axis.
This short-acting profile is why the DAC-free version is preferred in research protocols that specifically model pulsatile rather than continuous GHRH exposure.
Sourcing & purity
Research-grade material should be ≥99% pure by HPLC with peptide content confirmed via mass spectrometry. Redline Bio material ships with batch documentation; independent third-party COAs are published on the lab reports page as testing returns.
Compliance reminder
Sold and distributed for laboratory research use only. Not approved by the FDA for human consumption, diagnosis, treatment, or cure of any disease. Researchers are responsible for compliance with all applicable institutional, state, and federal regulations.
Frequently asked questions
What is CJC-1295 without DAC?
CJC-1295 without DAC is a 30-amino-acid tetrasubstituted analog of the first 29 residues of growth hormone releasing hormone (GHRH). The four substitutions (D-Ala², Gln⁸, Ala¹⁵, Leu²⁷) confer resistance to DPP-IV cleavage without extending half-life via albumin binding.
How does it differ from CJC-1295 with DAC?
The Drug Affinity Complex (DAC) version carries a maleimidopropionic acid linker that binds serum albumin, extending half-life to ~8 days. Without DAC, the half-life is ~30 minutes — producing a sharp, short GH pulse that mimics native GHRH signaling in research models.