The Drug Affinity Complex (DAC) is a molecular modification that binds to endogenous albumin, significantly extending the half-life of CJC-1295 in preclinical animal models[1]. The addition of DAC alters the molecular weight and binding affinity of CJC-1295, creating distinct pharmacokinetic profiles for long-term versus short-term preclinical observation[1][2]. Nautilus Peptides supplies the CJC-1295 No DAC variant at greater than 99% purity strictly for Research Use Only, and not for human consumption.
This guide explores the structural differences between CJC-1295 formulations with and without the Drug Affinity Complex. It details how the absence of DAC alters clearance rates, enabling researchers to investigate precise pulsatile release in controlled preclinical models.
What is the difference between CJC-1295 with DAC and without DAC?
The primary difference between CJC-1295 with DAC and without DAC is the presence of a maleimido-propionic acid linker that covalently binds to serum albumin, extending the peptide’s half-life from approximately 30 minutes to multiple days in preclinical models[1][3][4]. This structural addition alters the compound’s clearance rate and molecular weight, dictating its application in laboratory studies.
CJC-1295 with DAC contains an engineered Drug Affinity Complex attached to a lysine residue[3]. In circulation, this reactive maleimide group forms a stable thioether bond with the free thiol of cysteine-34 on endogenous albumin[3][5]. This shields the peptide from rapid enzymatic degradation. Consequently, the DAC-modified variant exhibits a terminal half-life of approximately 6 to 8 days in clinical and preclinical evaluations[5][4].
Conversely, CJC-1295 without DAC – often referred to as modified GRF 1-29 – lacks this albumin-binding moiety[1][6]. It relies solely on four amino acid substitutions for stability and does not measurably bind to endogenous albumin[1][2]. As a result, it clears rapidly, demonstrating a half-life of about 30 minutes in animal models[1][7]. The absence of the DAC group also lowers its molecular weight.
| Parameter | CJC-1295 With DAC | CJC-1295 No DAC |
|---|---|---|
| Molecular Weight | ~3,647 Da[8][9] | ~3,368 Da[10][6] |
| Albumin Binding | Covalent bond via Cys34[3][5] | None[1][6] |
| Preclinical Half-Life | ~6-8 days[5][4] | ~30 minutes[1][7] |
| Clearance Rate | Slow, prolonged exposure[11][12] | Fast, brief exposure[1][13] |
Researchers select variants based on the desired pharmacokinetic profile. Both compounds are strictly for Research Use Only and not intended for human consumption.
Why do researchers pair CJC-1295 No DAC with Ipamorelin in laboratory studies?
In laboratory studies, CJC-1295 No DAC exhibits a shorter clearance rate, allowing researchers to investigate precise pulsatile release when paired with Ipamorelin[1][14]. Because it does not bind to albumin, the No DAC variant clears from circulation rapidly, preventing the continuous, tonic elevation of growth hormone (GH) observed with long-acting analogs[7][13]. Nautilus Peptides supplies the CJC-1295 No DAC variant at greater than 99% purity strictly for Research Use Only, and not for human consumption.
Researchers investigate the CJC-1295 No DAC and Ipamorelin combination to study synergistic GH pulses through dual-pathway activation[14][15]. CJC-1295 No DAC acts as a growth hormone-releasing hormone (GHRH) analog, binding to the GHRH receptor on pituitary somatotrophs[1][7]. Ipamorelin functions as a selective ghrelin receptor (GHSR-1a) agonist[15][16]. When administered together in animal models, these compounds trigger a larger GH pulse than either agent alone[14][17].
The rapid clearance of CJC-1295 No DAC is critical for this preclinical mechanism. Ipamorelin induces a sharp GH peak approximately 0.5 to 1 hour post-administration[15][18]. The No DAC variant extends the amplitude of this specific pulse during its brief 30-minute half-life window[14][7]. Because the GHRH analog clears within a few hours, physiological metrics return toward baseline, preserving a natural pulsatile pattern rather than causing sustained systemic elevation[1][19]. This sequential activity profile makes the combination highly valuable for in vivo studies modeling discrete neuroendocrine signaling events without prolonged receptor desensitization.
Frequently Asked Questions
What is the difference between CJC-1295 with DAC and without DAC?
The primary difference is the Drug Affinity Complex (DAC). CJC-1295 with DAC covalently binds to endogenous albumin, extending its half-life to 6-8 days[3][4]. CJC-1295 without DAC lacks this complex, does not bind to albumin, and clears rapidly with a half-life of approximately 30 minutes in preclinical models[1][7].
How does the Drug Affinity Complex affect the half-life of CJC-1295?
The Drug Affinity Complex features a reactive maleimide group that forms a stable thioether bond with serum albumin[3][5]. This conjugation shields the peptide from enzymatic degradation, extending its half-life from minutes to multiple days in laboratory studies[2][4].
Why do researchers pair CJC-1295 No DAC with Ipamorelin?
Researchers pair them to investigate synergistic, pulsatile growth hormone release[14]. The short half-life of CJC-1295 No DAC amplifies the rapid GH spike induced by Ipamorelin without causing the multi-day hormone elevation seen with DAC-modified variants[7][13]. This combination is investigated strictly in Research Use Only contexts.
What is the molecular weight difference between the two CJC-1295 variants?
CJC-1295 with DAC has a molecular weight of approximately 3,647 Da due to the added albumin-binding moiety[8][9]. CJC-1295 without DAC has a lower molecular weight of approximately 3,368 Da[10][6]. Both variants are strictly for Research Use Only.
References
- CJC-1295 With DAC vs CJC-1295 No DAC: Key Differences in …. https://palmettopeptides.com/blogs/news/cjc1295-dac-vs-no-dac (2026-04-02)
- CJC-1295 DAC Peptide and Hormonal Regulation. https://www.corepeptides.com/cjc-1295-dac-peptide-and-hormonal-regulation/ (2024-07-26)
- CJC-1295 DAC Mechanism of Action: Albumin Binding Explained. https://palmettopeptides.com/blogs/news/cjc-1295-dac-mechanism-of-action-drug-affinity-complex-half-life (2026-05-18)
- Prolonged stimulation of growth hormone (GH) and insulin-like …. https://pubmed.ncbi.nlm.nih.gov/16352683/ (2006-03-06)
- CJC-1295 DAC 5mg Research Peptide | GHRH. https://palmettopeptides.com/products/cjc-1295-dac (2026-04-23)
- CJC-1295 No DAC – Luxe Peptides. https://luxepeptides.is/cjc-1295-no-dac/ (2026-02-13)
- CJC-1295: A Long-Acting GHRH Analog – Superpower. https://superpower.com/guides/cjc-1295 (2026-04-18)
- CJC-1295 DAC | CJC1295 DAC Peptide | High Purity – ProSpec Bio. https://prospecbio.com/products/cjc-1295-dac
- CJC-1295 – Wikipedia. https://en.wikipedia.org/wiki/CJC-1295 (2008-07-27)
- CJC1295 Without DAC | C152H252N44O42 | CID 91976842. https://pubchem.ncbi.nlm.nih.gov/compound/CJC1295-Without-DAC (2026-06-19)
- CJC 1295 DAC vs No DAC Netherlands : Key Differences. https://netherlands.pharmagrade.store/differences-in-cjc-1295-dac-vs-cjc-1295-no-dac/
- Differences in CJC-1295 vs Sermorelin for GHRH Delivery. https://biotechpeptides.com/2021/06/03/differences-in-cjc-1295-vs-sermorelin-for-ghrh-delivery/ (2021-06-03)
- CJC-1295 NO DAC for Sale – High-Purity Research Peptide. https://licensedpeptides.com/product/cjc-1295-no-dac/ (2026-06-11)
- CJC-1295 and Ipamorelin: A GHRH-Plus-Ghrelin … – Superpower. https://superpower.com/guides/cjc-1295-ipamorelin-stack (2026-04-18)
- Pharmacological Insights into the Ipamorelin & CJC-1295 Blend. https://biotechpeptides.com/2025/09/02/pharmacological-and-metabolic-insights-into-the-ipamorelin-cjc-1295-blend/ (2025-09-02)
- Ipamorelin/CJC-1295 and the Wolverine Stack (BPC-157/TB-500 …. https://rewellnesshub.com/exploring-peptide-therapies-ipamorelin-cjc-1295-and-the-wolverine-stack-bpc-157-tb-500-benefits-and-indications/ (2025-10-06)
- CJC-1295 + Ipamorelin Blend | ≥99% – Nationwide Peptides. https://www.nationwidepeptides.com/products/cjc-1295-ipamorelin-blend/ (2026-06-09)
- CJC-1295 + Ipamorelin | Benefits, Safety & Buying Advice [2026]. https://www.innerbody.com/cjc-1295-and-ipamorelin (2026-01-12)
- Is CJC-1295 / Ipamorelin FDA Approved? A Doctor Explains. https://olympiaaesthetics.com/cjc-1295-ipamorelin/ (2026-06-14)