GRF(1-29) comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2026-04-11. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white lyophilized powder | Visual descriptor; not a measure of purity |
| Solubility class | Freely soluble in water | Aqueous dissolution may require gentle mixing |
| Typical storage (powder) | −20 °C or below, desiccated | Protect from light and ambient moisture |
| Typical storage (solution) | 2–8 °C, short term | Freeze aliquots where longer holding is needed |
| Purity assessment | Reversed-phase HPLC, area percent | Values depend on column, gradient, and detection wavelength |
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.
Characterization of this peptide relies on a small set of routine techniques. Reversed-phase high-performance liquid chromatography separates the target from truncated or oxidized by-products and yields a purity estimate when paired with ultraviolet detection near 214 nanometers. Mass spectrometry, either electrospray coupled to liquid chromatography or matrix-assisted laser desorption, confirms that the observed mass matches the value calculated for the expected sequence. Amino acid analysis, and enzymatic digestion followed by fragment mapping, are used when the sequence itself rather than the mass requires verification.
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.
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.
== Formation and maintenance == The acidic pH at the skin's surface is mainly maintained by free amino acids and α-hydroxy acids (lactic acids) excreted from sweat; free fatty acids and amino acids from sebum; and urocanic acid and pyroglutamic acid.
== Toponym == The name of the town was attested in 1489, even before it was founded by François I in the form le Hable de Grace then Ville de Grace in 1516, two years before its official founding. The learned and transient name of Franciscopolis in tribute to the same king, is encountered in some documents then that of Havre Marat, referring to Jean-Paul Marat during the French Revolution but was not imposed. However it explains why the complementary determinant -de-Grace was not restored. This qualifier undoubtedly referred to the Chapel of Notre Dame located at the site of the cathedral of the same name. The chapel faced the Chapel Notre Dame de Grace of Honfleur across the estuary. The common noun havre meaning 'port' was out of use at the end of the 18th or beginning of the 19th centuries but is still preserved in the phrase havre de paix meaning 'safe haven'. It is generally considered a loan from Middle Dutch from the 12th century. A Germanic origin can explain the "aspiration" of the initial h. Havre de Grace, Maryland, in the United States retains the de Grace from colonial times. New research however focuses on the fact that the term was attested very early (12th century) and in Norman texts in the forms Hable, hafne, havene, havne, and haule makes a Dutch origin unlikely.
=== Chemical additives === Chemical additives are small chemical compounds that are added to the crystallization process to increase the yield of crystals. The role of small molecules in protein crystallization had not been well thought of in the early days since they were thought of as contaminants in most case. Small molecules are thought to help if/when they are incorporated as "packing bridges" in the crystal contact interfaces. It is currently not possible (as of 2017) to rationally determine what small molecules to use to improve chances of crystallization.
== Antidote == In case of a bite from the black mamba, the victim should be treated according to a standard protocol. The most important part of this treatment is the intravenous injection of a polyvalent antivenom. South African Vaccine Producers produces this antivenom. Polyvalent means that it can be used for different snakebites: vipers, mambas and cobras. Large quantities of the antivenom must be injected to counter the effects of the venom. The polyvalent antivenin is produced by injecting horses with adapted venom. The venom is first detoxified to prevent too much damage and death. This is mostly done by complexing the venom with an aldehyde like formalin. The venom is also administered with an adjuvant, like aluminium hydroxide or sodium alginate, to stimulate the immunological response. When the venom is injected, the body will produce antibodies. These will bind components – the variability of peptides – of the venom, which prevent further activity of the molecule and are ultimately removed by the immune system of the body. These antibodies are collected and purified from the blood and then packaged in mostly a liquid form. Horses are used because of the large blood volume. The final antivenom product expires after 5 years and needs to preferentially be kept cool, 4-8 °C. It can, however, survive different environmental situations for some weeks to months, without losing its potency. Because several venoms of different snakes are injected over time, the horse will develop different antibodies against all the venoms.
=== 15 April === Four people were killed by Russian shelling in Siversk, Donetsk Oblast. Two people were killed in a separate attack in Lukiantsi, Kharkiv Oblast. Ukrainian media reported that the Ukrainian military launched a missile attack on a Russian command post in Crimea. The partisan group Atesh claimed that the headquarters of the 810th Marine Brigade in Sevastopol was struck. Ukrainian border guards intercepted a Russian sabotage group trying to enter Sumy Oblast.
Sources: en.wikipedia.org
=== Shark repellent === P. marmoratas and P. pavoninus release pardaxin when threatened by sharks. Pardaxin targets the gills and pharyngeal cavity of the sharks. It results in severe struggling, mouth paralysis, and temporary increase of urea leakage in the gills. This distress is caused by the attack of the cellular membrane of the gills, which causes a large influx of salt ions. Research into creating a commercial shark repellent using pardaxin was discontinued because it dilutes in the water too quickly. It is only effective if sprayed almost directly into a shark's mouth.
=== Tumors === The tumor parenchyma, of a solid tumour, is one of the two distinct compartments in a solid tumour. The parenchyma is made up of neoplastic cells. The other compartment is the stroma induced by the neoplastic cells, needed for nutritional support and waste removal. In many types of tumour, clusters of parenchymal cells are separated by a basal lamina that can sometimes be incomplete.
==== Germany ==== The drug is in Appendix III of the Narcotics Act (Betäubungsmittelgesetz or BtMG). The law allows only physicians, dentists, and veterinarians to prescribe oxycodone and the federal government to regulate the prescriptions (e.g., by requiring reporting).
== Medical uses == In the United States, daptomycin is indicated for use in adults for skin and skin structure infections caused by Gram-positive infections, S. aureus bacteremia, and right-sided S. aureus endocarditis. In 2017, the FDA extended daptomycin's indications to pediatric patients aged 1 to 17 years: labeling for complicated skin and skin structure infections in this population was approved on 29 March 2017, and labeling for S. aureus bacteremia in pediatric patients was approved on 1 September 2017. Daptomycin is not recommended for patients younger than one year of age, given the potential for adverse effects on the muscular, neuromuscular, and nervous systems observed in neonatal animal studies. It binds avidly to pulmonary surfactant, and so is generally ineffective in treating pneumonia.
==== 5-HT system in vertebrates ==== Vertebrates are multicellular organisms in the phylum Chordata that possess a backbone and a nervous system. This includes mammals, fish, reptiles, birds, etc. In humans, the nervous system is composed of the central and peripheral nervous system, with little known about the specific mechanisms of neurotransmitters in most other vertebrates. However, it is known that while serotonin is involved in stress and behavioral responses, it is also important in cognitive functions. Brain organization in most vertebrates includes 5-HT cells in the hindbrain. In addition to this, 5-HT is often found in other sections of the brain in non-placental vertebrates, including the basal forebrain and pretectum. Since location of serotonin receptors contribute to behavioral responses, this suggests serotonin is part of specific pathways in non-placental vertebrates that are not present in amniotic organisms. Teleost fish and mice are organisms most often used to study the connection between serotonin and vertebrate behavior. Both organisms show similarities in the effect of serotonin on behavior, but differ in the mechanism in which the responses occur.
Sources: en.wikipedia.org
=== Pneumatic elevator === A pneumatic elevator consists of a cylindrical vertical shaft (typically made of transparent plastic), and a passenger capsule (also transparent) within the shaft which moves vertically by means of differential air pressure above and below. The main advantage that it requires neither a pit below or a loft above the shaft. For ascending operations, a vacuum pump at the top of the elevator shaft creates a low pressure by drawing air from above the capsule while below the greater normal atmospheric pressure is permitted to enter at the lower (ground floor) level below the capsule providing lift. To descend, electronically controlled valves inside the tubular shaft regulate the entry and exit of air within the cylinder lowering the car smoothly by means of programmed operation. In the event of a failure of the vacuum pump or electronically controlled valves, the trapped volume of air below the capsule acts as a cushion that is allowed to slowly escape by means of a mechanical valve, gently returning the capsule to the lowest level.
=== Control === A lot of effort has been put into controlling cell selectivity. For example, attempts have been made to modify and optimize the physicochemical parameters of the peptides to control the selectivities, including net charge, helicity, hydrophobicity per residue (H), hydrophobic moment (μ) and the angle subtended by the positively charged polar helix face (Φ). Other mechanisms like the introduction of D-amino acids and fluorinated amino acids in the hydrophobic phase are believed to break the secondary structure and thus reduce hydrophobic interaction with mammalian cells. It has also been found that Pro→Nlys substitution in Pro-containing β-turn antimicrobial peptides was a promising strategy for the design of new small bacterial cell-selective antimicrobial peptides with intracellular mechanisms of action. It has been suggested that direct attachment of magainin to the substrate surface decreased nonspecific cell binding and led to improved detection limit for bacterial cells such as Salmonella and E. coli.
=== Seizures by authorities === Authorities in Latvia and Lithuania reported seizing Carfentanil as an illicit drug in the early 2000s. Around 2016, the United States and Canada reported a dramatic increase in shipment of carfentanil and other strong opioid drugs to customers in North America from Chinese chemical supply firms. In June 2016, the Royal Canadian Mounted Police seized one kilogram of carfentanil shipped from China in a box labeled "printer accessories". According to the Canada Border Services Agency, the shipment contained 50 million potentially lethal doses of the drug, in containers labeled as toner cartridges for HP LaserJet printers. Carfentanil was not a controlled substance in China until 1 March 2017, and until then was manufactured legally and sold openly over the Internet, being actively marketed by several Chinese chemical companies.
Testosterone can be taken by a variety of different routes of administration. These include oral, buccal, sublingual, intranasal, transdermal (gels, creams, patches, solutions), vaginal (creams, gels, suppositories), rectal (suppositories), by intramuscular or subcutaneous injection (in oil solutions or aqueous suspensions), and as a subcutaneous implant. The pharmacokinetics of testosterone, including its bioavailability, metabolism, biological half-life, and other parameters, differ by route of administration. Likewise, the potency of testosterone, and its local effects in certain tissues, for instance the liver, differ by route of administration as well. In particular, the oral route is subject to a high first-pass effect, which results in high levels of testosterone in the liver and consequent hepatic androgenic effects, as well as low potency due to first-pass metabolism in the intestines and liver into metabolites like dihydrotestosterone and androgen conjugates. Conversely, this is not the case for non-oral routes, which bypass the first pass. Different testosterone routes and dosages can achieve widely varying circulating testosterone levels. For purposes of comparison with normal physiological circumstances, circulating levels of total testosterone in men range from about 250 to 1,100 ng/dL (mean 630 ng/dL) and in women range from about 2 to 50 ng/dL (mean 32 ng/dL). Testosterone levels decline with age in men.
Sources: en.wikipedia.org
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.
There is no single agreed limit, and laboratory practice varies widely. Refrigeration slows degradation, and freezing aliquots is often described for longer holding. Any visible cloudiness or precipitate indicates the solution should be discarded.
Mass spectrometry provides the most direct confirmation through molecular mass. Reversed-phase chromatography supports purity assessment, and peptide mapping or amino acid analysis can corroborate sequence. No single method establishes both purity and identity on its own.
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.