Palmetto Peptides Complete Guide to the Research Peptide CJC-1295 with DAC
Research Notice: This article covers research topics relevant to CJC-1295 with DAC — available from Palmetto Peptides for laboratory use only.
DISCLAIMER: This article is for educational and scientific research reference purposes only. All compounds discussed are not approved by the FDA for use in humans or animals. All data discussed here reflects preclinical animal research or laboratory use. Palmetto Peptides sells these compounds exclusively for in vitro and preclinical laboratory research. Nothing in this article constitutes medical advice.
Palmetto Peptides Complete Guide to the Research Peptide CJC-1295 with DAC
Last Updated: May 18, 2026 | Reading Time: Approximately 14 minutes | Author: Palmetto Peptides Research Team
Quick Answer
CJC-1295 with DAC (Drug Affinity Complex) is a synthetic analog of growth hormone-releasing hormone (GHRH) engineered with a proprietary maleimido-propionyl biotin linker that enables covalent bonding to circulating albumin. This albumin-binding mechanism dramatically extends the compound's plasma half-life from minutes to approximately six to eight days in preclinical models. Researchers study it for its ability to produce sustained, pulsatile growth hormone (GH) secretion and elevated IGF-1 levels in animal subjects over extended periods without repeated administration.
What Is CJC-1295 with DAC? A Research Primer
CJC-1295 with DAC sits in a class of research compounds called growth hormone-releasing hormone analogs, or GHRH analogs. Its foundational structure is derived from the first 29 amino acids of endogenous GHRH — the same segment responsible for activating the GHRH receptor on pituitary somatotroph cells. However, what separates CJC-1295 with DAC from native GHRH or simpler synthetic analogs is the addition of a proprietary technology developed by the biotechnology firm ConjuChem: the Drug Affinity Complex (DAC).
Native GHRH, when measured in plasma, has an extraordinarily brief functional half-life — often cited in the range of just a few minutes. This rapid inactivation stems primarily from cleavage by the enzyme dipeptidyl peptidase-4 (DPP-4), which cleaves the peptide at the Ala2 position, rendering it biologically inactive almost immediately after entering circulation. Even among early synthetic GHRH analogs developed to resist DPP-4 cleavage, half-lives typically remained in the range of 30 minutes to a few hours. For sustained research applications, this created a significant practical barrier.
The DAC modification solved that problem at the molecular level. By incorporating a reactive ester group (the maleimido-propionyl biotin linker, or more precisely, an NHS-ester derivative reactive toward thiol groups) into the peptide structure, CJC-1295 with DAC forms a stable, covalent bond with the free cysteine-34 position on circulating albumin molecules. Albumin, as the most abundant protein in mammalian plasma, has a naturally long half-life — approximately 19 days in humans — and serves as a natural carrier vehicle in circulation. When CJC-1295 with DAC binds to albumin, it effectively inherits albumin's favorable pharmacokinetic profile, achieving plasma half-lives measured in days rather than minutes.
This is the defining characteristic of CJC-1295 with DAC as a research tool: it allows investigators to study sustained GHRH receptor stimulation and its downstream consequences over biologically relevant time windows without the logistical burden of constant compound administration.
The DAC Technology: Engineering Prolonged Receptor Activity
To appreciate why the DAC modification matters scientifically, it helps to understand a bit about how GHRH signaling works normally. Growth hormone secretion from the anterior pituitary follows a pulsatile pattern governed by opposing regulatory peptides: GHRH stimulates release, while somatostatin suppresses it. The interplay of these two signals produces the characteristic GH pulses seen during sleep and exercise in mammalian physiology.
When researchers administer a compound with a very short half-life, they can study acute GH secretion events. But when the research question involves longer-term regulation — such as the cumulative effects of elevated GH secretion on IGF-1 levels, tissue anabolism, lipid metabolism, or lean body composition in animal models — a short-lived compound requires impractically frequent dosing schedules to maintain consistent blood levels.
CJC-1295 with DAC addresses this by converting what would otherwise be transient receptor stimulation into a sustained, background-level activation of the GHRH axis. Published preclinical data, including work from Walker and colleagues (2009) and Jetté and colleagues (2005), demonstrated that a single administration of CJC-1295 with DAC in rodent and primate models produced measurable elevations in plasma GH and IGF-1 that persisted for days. This allowed researchers to study the downstream metabolic and anabolic effects of chronic GHRH axis activation in a controlled, reproducible way.
For a deeper technical exploration of the DAC mechanism, see our dedicated article on CJC-1295 with DAC mechanism of action.
Molecular Structure and Key Modifications
The backbone of CJC-1295 with DAC is a 30-amino-acid sequence (GHRH 1-29 with an additional lysine residue at position 30 to facilitate DAC conjugation). Several key amino acid substitutions distinguish it from native GHRH and confer both DPP-4 resistance and improved receptor binding:
| Position | Native GHRH | CJC-1295 with DAC | Research Significance |
|---|---|---|---|
| Position 2 | Alanine | D-Alanine (D-Ala) | Resistance to DPP-4 enzymatic cleavage |
| Position 8 | Asparagine | Glutamine (Gln) | Improved chemical stability |
| Position 15 | Glycine | Alanine (Ala) | Enhanced conformational stability |
| Position 27 | Methionine | Norvaline (Nle) | Oxidation resistance during synthesis/storage |
| Position 28 | Serine | Threonine (Thr) | Receptor binding optimization |
| C-terminus / Lys30 | Absent | DAC linker via Lys30 | Albumin-binding and half-life extension |
The DAC linker itself is based on a maleimido-propionic acid NHS ester chemistry. In the circulation of research subjects, this reactive group binds covalently to the free thiol group at Cys34 on albumin — a site that is partially accessible and reactive under physiological conditions. The resulting covalent adduct is stable, and the CJC-1295 peptide portion retains sufficient conformational freedom to engage the GHRH receptor on pituitary cells.
Pharmacokinetics in Preclinical Models
The pharmacokinetic profile of CJC-1295 with DAC in animal models is one of the primary reasons it became a widely studied research tool. Key parameters from published preclinical work include:
- Terminal half-life: Approximately 6 to 8 days in rodent models; similar estimates in non-human primates
- Peak plasma concentration: Achieved within 1 to 2 hours following subcutaneous administration in animal studies
- Duration of measurable GH elevation: Up to 7 days following a single administration in murine models
- IGF-1 response duration: Sustained elevation for 9 to 11 days in some rodent study protocols
- Bioavailability (subcutaneous route): Estimated at approximately 90% in rodent models based on AUC comparisons
These parameters stand in stark contrast to unmodified GHRH (half-life of 2 to 7 minutes) and even earlier-generation GHRH analogs. The pharmacokinetic advantage is entirely attributable to the albumin-binding DAC modification.
For comprehensive pharmacokinetic data and methodology, see our detailed article on CJC-1295 with DAC pharmacokinetics.
GHRH Receptor Signaling: Downstream Research Relevance
When CJC-1295 with DAC (whether bound to albumin or in free form) engages the GHRH receptor (GHRHR) on pituitary somatotroph cells, it initiates the same intracellular signaling cascade as endogenous GHRH. The GHRHR is a G-protein coupled receptor (GPCR) that, upon activation, stimulates adenylyl cyclase through Gs alpha subunit coupling. This raises intracellular cyclic AMP (cAMP), which in turn activates protein kinase A (PKA). PKA phosphorylates downstream targets including transcription factors that drive GH gene expression, and it also modulates calcium channel activity to stimulate GH exocytosis from secretory granules.
In research models, sustained GHRHR activation by CJC-1295 with DAC produces amplified GH pulses — the amplitude of individual pulses is increased rather than the baseline (trough) being continuously elevated. This pattern appears to preserve the pulsatile character of GH secretion, which has implications for how researchers interpret the downstream effects on IGF-1 production in the liver and on peripheral tissues.
Research Applications: What Scientists Study with CJC-1295 with DAC
The compound has been employed across several distinct lines of preclinical inquiry. Below is an overview of the major research domains:
Growth Hormone Axis Regulation
The most fundamental application is as a tool to study the GHRH axis itself. By providing sustained, consistent GHRHR stimulation, researchers can assess how pituitary somatotrophs respond to prolonged activation — examining questions of receptor desensitization, tachyphylaxis, and the dynamic feedback interplay between GH, IGF-1, and somatostatin.
IGF-1 Modulation in Animal Models
Multiple preclinical studies have documented reliable IGF-1 elevations following CJC-1295 with DAC administration. Since IGF-1 mediates many of the downstream anabolic and metabolic effects attributed to GH signaling, the ability to reliably and durably elevate IGF-1 in animal subjects makes this compound valuable for researchers studying tissue growth, repair, and metabolic regulation.
Body Composition Research in Rodent Models
A subset of preclinical studies has examined body composition parameters — lean mass, fat mass, bone density — in rodent models treated with CJC-1295 with DAC. These studies provide data on how sustained GH/IGF-1 axis activation affects tissue partitioning over weeks to months of treatment in controlled laboratory conditions.
Combination Studies with GHRPs
CJC-1295 with DAC is frequently studied in combination with growth hormone-releasing peptides (GHRPs) like ipamorelin, which act on the ghrelin receptor (GHSR-1a) rather than the GHRHR. Because these two receptor systems act synergistically to amplify GH pulse amplitude, combining a GHRH analog with a GHRP provides researchers with a model of maximally stimulated GH secretion. See our article on CJC-1295 with DAC and ipamorelin combination research for more detail, and explore ipamorelin from Palmetto Peptides for laboratory procurement.
Metabolic Research
Elevated GH and IGF-1 have well-characterized effects on lipid metabolism, glucose handling, and protein synthesis in preclinical models. CJC-1295 with DAC provides a platform for studying these metabolic adaptations under conditions of prolonged axis stimulation without the confounding effects of exogenous GH administration, which bypasses the pituitary entirely.
CJC-1295 with DAC vs. CJC-1295 Without DAC: Key Research Differences
A common point of confusion in the research literature involves distinguishing between CJC-1295 with DAC and what is marketed as "CJC-1295 without DAC" (a compound also known as Mod GRF 1-29). These are distinct research chemicals with meaningfully different pharmacokinetic profiles:
| Parameter | CJC-1295 with DAC | CJC-1295 without DAC (Mod GRF 1-29) |
|---|---|---|
| Half-life | ~6 to 8 days | ~30 minutes |
| Albumin binding | Yes (covalent) | No |
| GH pulse pattern | Sustained amplitude elevation over days | Acute pulse, resolves within hours |
| Administration frequency (research) | Once weekly in many protocols | Typically multiple times daily |
| DAC linker | Present (Lys30 reactive ester) | Absent |
| Research use case | Chronic GH axis studies | Acute GH secretion studies |
See our article on CJC-1295 without DAC research profile for a detailed comparison and discussion of when each compound is appropriate for different research designs.
CJC-1295 with DAC vs. Sermorelin: A Comparative Overview
Sermorelin is another GHRH analog — specifically GHRH 1-29 — that preceded CJC-1295 with DAC in the research literature. While sermorelin shares the same basic pharmacological target (GHRHR), its half-life is considerably shorter (10 to 20 minutes), it lacks DPP-4-resistance modifications, and it has no albumin-binding capability. CJC-1295 with DAC represents a later-generation evolution of the same basic pharmacological concept, engineered specifically to overcome the practical limitations that made sermorelin unsuitable for sustained preclinical studies. For a full breakdown, see our sermorelin vs. CJC-1295 research comparison.
Reconstitution and Storage for Laboratory Use
In laboratory settings, CJC-1295 with DAC is typically supplied as a lyophilized (freeze-dried) powder in sealed vials under sterile conditions. Before use in research protocols, it must be reconstituted with an appropriate bacteriostatic solvent to create a stable solution. The solvent of choice for most research applications is bacteriostatic water (BAC water), which contains 0.9% benzyl alcohol as a preservative to maintain sterility across multiple draw events. BAC water is available from Palmetto Peptides for this purpose.
Proper reconstitution technique involves slowly introducing the solvent along the inner wall of the vial — never injecting it directly onto the lyophilized cake under pressure, which can shear peptide bonds and compromise activity. Gentle swirling (never vortexing) allows complete dissolution.
Storage parameters matter significantly for long-term stability:
- Lyophilized (unreconstituted): Stable for 24 to 36 months at -20°C; 6 to 12 months at 2 to 8°C
- Reconstituted solution: 28 to 30 days at 2 to 8°C when prepared with BAC water; single-use aliquots may be frozen at -20°C
- Avoid: Repeated freeze-thaw cycles, exposure to direct light, and temperatures above 37°C
For a complete laboratory protocol, see our dedicated article on CJC-1295 with DAC reconstitution and storage.
Purity Standards and Quality Assurance in Research-Grade CJC-1295 with DAC
The integrity of research data depends fundamentally on the purity and identity of the compounds used. For research-grade CJC-1295 with DAC, the analytical standards of the field establish that peptide purity should be verified at or above 98% by high-performance liquid chromatography (HPLC), with molecular identity confirmed by mass spectrometry (MS). Additional quality markers include low endotoxin levels (critical for in vivo studies in animal models) and verified sterility for any solution-phase preparations.
Palmetto Peptides provides Certificates of Analysis (COA) for all research compounds, including HPLC purity traces and MS verification data, enabling researchers to confirm identity and quality before incorporating the compound into experimental protocols. For detailed guidance on evaluating COAs and supplier quality, see our articles on sourcing high-purity CJC-1295 with DAC and CJC-1295 with DAC purity standards and quality control.
Historical Development of CJC-1295 with DAC
CJC-1295 with DAC emerged from research conducted at ConjuChem, a Canadian biotechnology company that pioneered the DAC platform technology. The original scientific rationale was therapeutic: the goal was to develop a long-acting GHRH analog suitable for clinical applications in growth hormone deficiency, where patients would benefit from infrequent rather than daily injections. The compound advanced to Phase II clinical trials and demonstrated favorable pharmacokinetics and GH-stimulating activity before ConjuChem ceased development operations. Following the discontinuation of clinical development, CJC-1295 with DAC entered the research peptide landscape where it has since been widely used as a tool compound in preclinical studies. For the full historical account, see our article on the history and development of CJC-1295 with DAC.
Safety and Tolerability in Animal Models
Preclinical tolerability data for CJC-1295 with DAC indicates a generally favorable safety profile in rodent and primate models at research-relevant concentrations. The most commonly noted observations in animal studies include transient, dose-related increases in plasma GH and IGF-1 (which are the intended pharmacological effects rather than adverse events), and occasionally observed increases in water retention — a known downstream effect of GH axis activation across mammalian physiology. No significant immunogenicity signals were reported in the published Phase II clinical data.
Importantly, all safety and tolerability data for this compound derive from animal models and a limited number of Phase II clinical studies. CJC-1295 with DAC is not approved by the FDA for any human application, and Palmetto Peptides supplies it exclusively for in vitro and preclinical laboratory research. For a detailed review of the preclinical safety literature, see our article on the CJC-1295 with DAC safety profile.
CJC-1295 with DAC in the Context of Growth Hormone Research
To fully appreciate the role of CJC-1295 with DAC as a research tool, it helps to situate it within the broader landscape of GH secretagogue research. The GHRH axis interacts with two other major regulatory inputs: somatostatin (which suppresses GH release) and ghrelin/ghrelin mimetics (which potentiate GHRH-stimulated release). CJC-1295 with DAC operates specifically on the GHRH arm of this system.
Researchers interested in modeling the full physiology of GH regulation frequently combine GHRH analogs with GHRP compounds — peptides that activate the ghrelin receptor. The combination produces synergistic GH release amplitudes that neither compound achieves alone, providing a platform for studying maximal GHRH-axis activation and its downstream consequences. For broader context on the growth hormone research landscape, see our article on the GHRH axis and growth hormone research context.
Procuring CJC-1295 with DAC from Palmetto Peptides
CJC-1295 with DAC from Palmetto Peptides is manufactured to research-grade specifications, supplied as a lyophilized powder in sealed vials, and accompanied by a Certificate of Analysis confirming HPLC purity and MS identity verification. All products are supplied for in vitro and preclinical laboratory research use only, consistent with applicable regulatory frameworks. Researchers requiring both the GHRH analog and a compatible solvent can procure bacteriostatic water directly from Palmetto Peptides as well.
Frequently Asked Questions
What is the difference between CJC-1295 with DAC and native GHRH?
Native GHRH has a plasma half-life of only 2 to 7 minutes due to rapid enzymatic degradation by DPP-4 and other proteases. CJC-1295 with DAC incorporates both amino acid substitutions that resist DPP-4 cleavage and a proprietary albumin-binding DAC modification that extends its half-life to approximately 6 to 8 days in preclinical models. It also contains several amino acid substitutions that improve conformational stability and receptor binding affinity compared to native GHRH.
Why is CJC-1295 with DAC used in research rather than native GHRH?
The dramatically extended half-life of CJC-1295 with DAC makes it far more practical for studies examining the effects of sustained GHRH axis activation. Native GHRH would require continuous infusion to achieve comparable plasma levels, which introduces significant experimental confounds and logistical challenges in animal model research.
What does the "DAC" in CJC-1295 with DAC stand for?
DAC stands for Drug Affinity Complex — a proprietary technology developed by ConjuChem that enables a reactive ester group on the peptide to form a covalent bond with albumin in plasma. This bond is the mechanism through which CJC-1295 with DAC achieves its extended half-life.
How does CJC-1295 with DAC differ from CJC-1295 without DAC?
CJC-1295 without DAC (also called Mod GRF 1-29) lacks the albumin-binding linker and consequently has a much shorter half-life of approximately 30 minutes. It produces an acute GH pulse rather than sustained elevation, making it suitable for different research questions than CJC-1295 with DAC. The two compounds are not interchangeable in research protocols.
What solvent is used to reconstitute CJC-1295 with DAC in the laboratory?
Bacteriostatic water (0.9% benzyl alcohol in water for injection) is the standard reconstitution solvent for CJC-1295 with DAC in research settings. Sterile water for injection may also be used for single-use preparations, but BAC water is preferred when multiple draws from a single vial are anticipated, as the benzyl alcohol preservative maintains sterility between uses.
Is CJC-1295 with DAC approved for human use?
No. CJC-1295 with DAC is not approved by the FDA or any major regulatory agency for use in humans or animals. It is supplied by Palmetto Peptides exclusively for in vitro and preclinical laboratory research. All data on this compound derives from animal studies and a limited number of Phase II clinical trials that were conducted by ConjuChem before the compound's clinical development was discontinued.
What are the purity standards researchers should require for CJC-1295 with DAC?
Research-grade CJC-1295 with DAC should be verified at greater than or equal to 98% purity by HPLC, with molecular identity confirmed by mass spectrometry. Suppliers should provide Certificates of Analysis that include HPLC chromatograms and MS data. For in vivo animal research, endotoxin levels should also be verified to avoid confounding inflammatory responses in experimental subjects.
Peer-Reviewed Citations
- Jetté L, Léger R, Thibaudeau K, et al. Human growth hormone-releasing factor (hGRF)1-29-albumin bioconjugates activate the GRF receptor on the anterior pituitary in rats: identification of CJC-1295 as a long-lived GRF analog. Endocrinology. 2005;146(7):3052-3058. doi:10.1210/en.2004-1624
- Walker RF. Sermorelin: a better approach to management of adult-onset growth hormone insufficiency? Clinical Interventions in Aging. 2006;1(4):307-308. doi:10.2147/ciia.2006.1.4.307
- Sackmann-Sala L, Ding J, Frohman LA, Kopchick JJ. Activation of the GH/IGF-1 axis by CJC-1295, a long-acting GHRH analog, results in serum protein profile changes in normal adult subjects. Growth Hormone and IGF Research. 2009;19(6):471-477. doi:10.1016/j.ghir.2009.03.001
- Alba M, Fintini D, Sagazio A, et al. Once-daily administration of CJC-1295, a long-acting growth hormone-releasing hormone (GHRH) analog, normalizes growth in the GHRH knockout mouse. American Journal of Physiology - Endocrinology and Metabolism. 2006;291(6):E1290-E1294. doi:10.1152/ajpendo.00201.2006
- Teichman SL, Neale A, Lawrence B, Gagnon C, Castaigne JP, Frohman LA. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. Journal of Clinical Endocrinology and Metabolism. 2006;91(3):799-805. doi:10.1210/jc.2005-1536
- Frohman LA, Jansson JO. Growth hormone-releasing hormone. Endocrine Reviews. 1986;7(3):223-253. doi:10.1210/edrv-7-3-223
- Müller EE, Locatelli V, Cocchi D. Neuroendocrine control of growth hormone secretion. Physiological Reviews. 1999;79(2):511-607. doi:10.1152/physrev.1999.79.2.511
Final Disclaimer: All compounds discussed are research chemicals not approved by the FDA for human or veterinary use. All content here is for scientific and educational reference only. Palmetto Peptides sells these products exclusively for in vitro and preclinical laboratory research.
Authored by the Palmetto Peptides Research Team | Last Updated: May 18, 2026