DAC is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2025-11-11. Where a claim depends on a specific study, the study is described rather than over-claimed.
Naming in this area is inconsistent, and readers should treat product labels with care. In much of the literature and in vendor catalogs, the unqualified term refers to the albumin-binding version, while the version lacking the DAC group appears as modified GRF(1-29), mod GRF(1-29), or the same name with a without-DAC qualifier. Because one abbreviation has been applied to both materials, the only reliable way to identify a sample is to check the stated sequence and the presence of the linker.
CJC-1295 is the name used for a synthetic peptide modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. The compound was described by a Canadian drug discovery company in the mid-2000s as a long-acting research tool. Two closely related molecules share the name in practice: one carries a drug affinity complex, or DAC, group, and one does not. The distinction matters because the two behave differently in circulation.
The peptide backbone corresponds to GRF(1-29), the first 29 residues of native growth hormone-releasing hormone, which retains most of the receptor-activating activity of the full-length molecule. Four substitutions distinguish the analog from the natural sequence: D-alanine at position 2, glutamine at position 8, alanine at position 15, and leucine at position 27. These changes slow cleavage by dipeptidyl peptidase IV, the enzyme that degrades native hormone in plasma within minutes. The outcome is improved enzymatic stability combined with a still brief residence time when no additional modification is present.
Reconstitution is typically performed with sterile water or bacteriostatic water, added slowly against the vial wall. The resulting solution should be clear and colorless; cloudiness or visible particles suggest a problem with the material or the diluent. Once in solution, the peptide is less stable than the dry powder. Refrigerated storage at two to eight degrees Celsius is common for short-term holding, while freezing aliquots is described for longer periods.
Purity is most often assessed by reversed-phase high-performance liquid chromatography, reported as a percentage of total peak area. Identity is confirmed by mass spectrometry, which yields a molecular ion consistent with the expected sequence. Amino acid analysis and peptide mapping provide additional characterization. Reported purity values are method-dependent, so figures from different laboratories are not always directly comparable without details of column, gradient, and detection wavelength.
Peptide degradation proceeds mainly through hydrolysis, oxidation of methionine, and deamidation of asparagine or glutamine residues. The maleimide group on the albumin-binding variant can also react with thiols or hydrolyze in aqueous media. Because these pathways accelerate with temperature and pH extremes, handling conditions strongly influence measured stability. Stability data in the public literature are limited and often generated under differing conditions, so general statements about shelf life should be read as approximate.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic peptide | GHRH analog, not a steroid |
| Backbone length | 29 amino acids | Based on GRF(1-29) |
| Substitutions | Four positions | D-Ala2, Gln8, Ala15, Leu27 |
| Appearance | White to off-white powder | Typical lyophilized research material |
| Common synonyms | Modified GRF(1-29) | Usage varies between sources |
Identity and purity are established with reversed phase high performance liquid chromatography coupled to mass spectrometry. The chromatographic step separates the target peptide from truncated sequences and deletion products, while the mass measurement confirms the expected molecular weight to within a fraction of a dalton. Because the two common variants differ by the presence of the linker, mass alone can distinguish them in the unconjugated state. Amino acid analysis and peptide mapping are used when sequence level confirmation is required.
Lyophilized material is generally stable for extended periods when held at minus twenty degrees Celsius or below and protected from moisture and light. In solution the peptide is more labile; bond hydrolysis, aggregation and oxidation of susceptible residues all proceed faster at ambient temperature. Repeated freeze and thaw cycles should be avoided because they promote clumping and loss of soluble material. The conjugated variant adds a further consideration, since the maleimide group can hydrolyze in aqueous buffer and lose its ability to react with albumin.
CJC-1295 is a synthetic peptide analog of growth hormone-releasing hormone, constructed on the 29-amino-acid fragment designated GRF(1-29). The name began as an internal development code during the 1990s and later spread through research supply catalogs and discussion forums. The molecule does not occur in nature; its sequence is engineered rather than isolated from tissue. Two related compounds are sold under this single label, and they differ by one appended chemical group that strongly influences how long the peptide remains in circulation.
The dividing feature between the two forms is a maleimide-based drug affinity complex, abbreviated DAC. In the DAC-bearing version, a linker attaches the peptide to serum albumin after administration, and that association slows removal from plasma. The version lacking DAC appears in catalogs as MOD GRF(1-29) or tetrasubstituted GRF(1-29). Because informal writing treats both as one item, comparisons drawn from such sources routinely blend measurements taken from two molecules with substantially different behavior.
Four amino acid substitutions separate the modified backbone from the parent GRF(1-29) sequence. These changes reduce recognition by dipeptidyl peptidase IV and related proteases, extending the interval before degradation. Development work in this area sought longer-acting GHRH analogs for endocrine investigation. Published descriptions treat the substitution set as a defining property of the core sequence, while the albumin-binding linker is described separately as an optional addition to that same backbone.
Stability depends heavily on physical state. A lyophilized powder kept dry, desiccated, and shielded from light typically holds its integrity for months to years at minus twenty degrees Celsius, and longer at minus eighty. Once dissolved, the peptide becomes far more vulnerable, since peptide bond hydrolysis, oxidation of susceptible residues, and aggregation all proceed faster in solution. Buffers near neutral pH are generally gentler than strongly acidic or alkaline conditions. Repeated freeze-thaw cycles and exposure to air-liquid interfaces during vigorous mixing cause losses that are easy to overlook.
Verification matters because research peptides vary widely in quality. A certificate of analysis is only as reliable as the method behind it, and a single chromatographic trace reveals little about counter-ions, residual solvents, or water content. Independent laboratories commonly pair mass confirmation with chromatographic purity and, where relevant, quantify water along with acetate or trifluoroacetate content. Reported purity figures are not standardized across suppliers, so a stated value such as ninety-eight percent is not directly comparable unless the analytical method, column, and detection wavelength accompany it.
=== Drug product development and manufacturing === The company offers formulation development, analytical testing, solid-form screening, and clinical-stage manufacturing for oral and parenteral dosage forms. BioDuro also operates high-potency manufacturing suites for highly potent compounds and cytotoxics.
Type 1: An aggressive form of the disease found in only 3% of people with Dupuytren's, which can affect men under 50 with a family history of Dupuytren's. It is often associated with other symptoms such as knuckle pads and Ledderhose disease. This type is sometimes known as Dupuytren's diathesis. Type 2: The more normal type of Dupuytren's disease, usually found in the palm only, and which generally begins above the age of 50. This type may be made more severe by other factors such as diabetes or heavy manual labor. Type 3: A mild form of Dupuytren's which is common among diabetics or which may also be caused by certain medications, such as the anti-convulsants taken by people with epilepsy. This type does not lead to full contracture of the fingers, and is probably not inherited.
SEM images of the radula can be found at Thompson, T.E.; Bebbington, A. (1973). "Scanning electron microscope studies of gastropod radulae". Malacologia. 14: 147–165. Tucker J.K. (2009). Recent cone species database. September 4th 2009 Edition Filmer R.M. (2001). A Catalogue of Nomenclature and Taxonomy in the Living Conidae 1758–1998. Backhuys Publishers, Leiden. 388pp Bouchet, P.; Fontaine, B. (2009). "List of new marine species described between 2002–2006". Census of Marine Life. Natural History Museum Rotterdam - photos of Conus shells Archived 2015-06-09 at the Wayback Machine Cone snail and conotoxins page The Conus Biodiversity website ConoServer Conidae from worldwide.conchology.com. Scroll down for many photographs. Pain-killer comes out of its shell (The Age news article) Venomous snails aid medical science (BBC News Article). ConeShell Collection Giancarlo Paganelli Archived 2019-12-21 at the Wayback Machine Cone Shells - Knights of the Sea. Alexander Medvedev's collection Cone Snail Video - Hunting Footage and Physiology Deadly Critters That Might Save Your Life (CNN) Baldomero "Toto" Olivera's short talk: Conus Peptides Archived 2015-04-06 at the Wayback Machine Zonatus Gallery Miller, John A. (1989). "The toxoglossan proboscis: structure and function". Journal of Molluscan Studies. 55 (2): 167–181. doi:10.1093/mollus/55.2.167. BBC Nature Video Cone snails are silent assassins of the sea, drugging sleeping fish before poisoning them Cone Snail Venom and AI May Lead to Drug Discovery | LANL
Dragian Ganymede (ドラグ星人ガニメデ, Doragu Seijin Ganimede): A crab-themed criminal from Planet Drag whom Agent Abrella broke out of prison and equipped with a Hyper Muscle Gear to assist him in attacking the Deka Base, only to be deleted by Deka Blue and Green. Ganymede is voiced by Yūji Kishi (岸 祐二, Kishi Yūji). Jergonian Sukeela (ジャーゴ星人スキーラ, Jāgo Seijin Sukīra): A mantis shrimp–themed criminal from Planet Jergo whom Agent Abrella broke out of prison and equipped with a Hyper Muscle Gear to assist him in attacking the Deka Base, only to be deleted by Deka Yellow and Pink. Sukeela is voiced by Emi Shinohara (篠原 恵美, Shinohara Emi).
Sources: en.wikipedia.org
Progesterone (P4), sold under the brand name Prometrium among others, is a medication and naturally occurring steroid hormone. It is a progestogen and is used in combination with estrogens mainly in hormone therapy for menopausal symptoms, and low sex hormone levels in women, as well as gender affirming therapy in transgender women. It is also used in women to support pregnancy and fertility and to treat gynecological disorders. Progesterone can be taken by mouth, vaginally, and by injection into muscle or fat, among other routes. A progesterone vaginal ring and progesterone intrauterine device used for birth control also exist in some areas of the world. Progesterone is well tolerated and often produces few or no side effects. However, a number of side effects are possible, for instance mood changes. If progesterone is taken by mouth or at high doses, certain central side effects including sedation, sleepiness, and cognitive impairment can also occur. The medication is a naturally occurring progestogen and hence is an agonist of the progesterone receptor (PR), the biological target of progestogens like endogenous progesterone. It opposes the effects of estrogens in various parts of the body like the uterus and also blocks the effects of the hormone aldosterone. In addition, progesterone has neurosteroid effects in the brain. Progesterone was first isolated in pure form in 1934. It first became available as a medication later that year. Oral micronized progesterone (OMP), which allowed progesterone to be taken by mouth, was introduced in 1980.
HATU (Hexafluorophosphate Azabenzotriazole Tetramethyl Uronium) is a reagent used in peptide coupling chemistry to generate an active ester from a carboxylic acid. HATU is used along with Hünig's base (N,N-diisopropylethylamine), or triethylamine to form amide bonds. Typically dimethylformamide is used as solvent, although other polar aprotic solvents can also be used.
The key intermediate step of these cyclometalation reactions involves the metal-mediated cleavage of the C–H bond and simultaneous formation of the metal–C bond of the substrate. Upon addition of substrate, the N-acyl motif acts as an internal proton acceptor in the concerted metal-deprotonation (CMD) of the transition state for this inner-sphere process. According to this model, the rate and selectivity of the C–H functionalization are impacted by the basicity of the MPAA ligand. The resulting experimental data of steric and electronic alteration of the MPAA ligands align with this model. In 2023, the first experimental observations to support the proposed mechanism were reported, which were previously unattainable due to the lack of well-defined isolated palladium-MPAA complexes.
Sources: en.wikipedia.org
No. It is a laboratory-made analog of growth hormone-releasing hormone. The natural hormone is a 44-residue peptide, while the analog is built on a shorter 29-residue fragment.
The original material included a linker that binds serum albumin. A later variant removed that linker to reduce the duration of action. Catalogs and papers did not consistently adopt separate names, so both remain widely labeled with the same term.
The amino acid sequence and the presence or absence of the linker group. Mass measured by spectrometry gives an independent check that separates the two forms.
Cool, dark, and dry conditions are standard, with storage at minus twenty degrees Celsius or below. Desiccant and sealed vials limit moisture uptake. Repeated warming and cooling of the container is generally avoided.