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 2026-04-26. Numbers and descriptions here follow the published literature rather than marketing material.
Two forms circulate under the CJC-1295 name, and they differ by a single appended group. The version without a drug affinity complex carries four substitutions along the peptide chain, including a D-alanine near the amino terminus and replacements at three other positions. These changes block the enzyme dipeptidyl peptidase IV and remove a methionine residue that is prone to oxidation. The modified fragment is frequently labeled MOD GRF 1-29. Naming conventions are inconsistent across informal sources, which is a common source of confusion.
The second form adds a maleimide-bearing linker to the lysine at the carboxyl end. This group reacts with cysteine-34 on circulating serum albumin, forming a covalent bond that keeps the peptide in the bloodstream for far longer. ConjuChem developed the molecule as a way to extend the action of a peptide without frequent administration. The albumin attachment is the defining structural feature of the drug affinity complex version. Whether continuous exposure produces effects distinct from shorter pulses remains an unresolved research question.
Two forms circulate in research settings and are frequently confused. One carries the drug affinity complex and is often written as CJC-1295 with DAC; the other lacks that group and is usually called modified GRF(1-29). The two share the same core sequence but differ sharply in how long they persist in blood. Products labelled only as CJC-1295 normally refer to the version carrying the complex. Documentation that omits the distinction leaves the intended molecule ambiguous.
CJC-1295 is a synthetic peptide built as a long-acting analogue of growth hormone-releasing hormone. Its backbone matches the first twenty-nine residues of the natural human hormone, with four amino acid substitutions added to slow enzymatic breakdown. A reactive maleimide group, commonly termed the drug affinity complex, allows the peptide to attach to circulating albumin after administration. That albumin attachment keeps the molecule in the bloodstream for an extended period instead of being cleared within minutes.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C152H252N44O42 | Cited for the form without the drug affinity complex |
| Molecular weight | About 3368 Da | Reported value for modified GRF(1-29) |
| Appearance | White to off-white powder | Lyophilised solid as usually supplied |
| Solubility | Soluble in water and polar solvents | Clarity depends on purity and salt content |
| Typical storage | -20 C or below, dry | Protect from light and repeated warming cycles |
The drug affinity complex is a maleimidopropionic acid group attached to a lysine side chain. It reacts with the free thiol of cysteine-34 on circulating albumin, forming a covalent bond. This conjugation keeps the peptide in the bloodstream and shields it from rapid renal filtration and proteolysis. Reported circulation half-lives for the albumin-bound form fall in the range of roughly six to nine days in early human studies.
Binding to GHRH receptors on pituitary somatotroph cells triggers cyclic AMP signaling and stimulates growth hormone synthesis and release. Because the peptide acts upstream of the pituitary, effects are mediated through endogenous growth hormone rather than direct receptor activation in peripheral tissues. Increases in insulin-like growth factor 1 are generally described as a downstream consequence. Most published human exposure data come from small early-stage studies, and the clinical significance of the pharmacokinetic profile remains incompletely characterized.
CJC-1295 is a synthetic analogue of growth hormone-releasing hormone, built on the 29-amino-acid GHRH(1-29) fragment. Four substitutions distinguish it from the natural sequence: D-alanine at position 2, glutamine at position 8, alanine at position 15, and leucine at position 27. These changes reduce enzymatic cleavage and extend the peptide's persistence in circulation. The compound is discussed in two forms, one carrying a drug affinity complex and one without it.
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.
In 1908, helium was first liquefied by Dutch physicist Heike Kamerlingh Onnes by cooling the gas to less than 5 K (−268.15 °C; −450.67 °F). He tried to solidify it by further reducing the temperature but failed, because helium does not solidify at atmospheric pressure. Onnes' student Willem Hendrik Keesom was eventually able to solidify 1 cm3 of helium in 1926 by applying additional external pressure. In 1913, Niels Bohr published his "trilogy" on atomic structure that included a reconsideration of the Pickering–Fowler series as central evidence in support of his model of the atom. This series is named for Edward Charles Pickering, who in 1896 published observations of previously unknown lines in the spectrum of the star ζ Puppis (these are now known to occur with Wolf–Rayet and other hot stars). Pickering attributed the observation (lines at 455.1, 541.1, and 1012.3 nm) to a new form of hydrogen with half-integer transition levels. In 1912, Alfred Fowler managed to produce similar lines from a hydrogen-helium mixture, and supported Pickering's conclusion as to their origin. Bohr's model does not allow for half-integer transitions (nor does quantum mechanics) and Bohr concluded that Pickering and Fowler were wrong, and instead assigned these spectral lines to ionised helium, He+.
===== Venezuela ===== In May 2023, ahead of a South American summit to which all the presidents of the region were invited, Lula met with Venezuelan president Nicolás Maduro and stated that "you know the narrative that was built against Venezuela, of anti-democracy, of authoritarianism" and "it is in your hands, comrade, to build your narrative and turn this party around so that we can definitively win and Venezuela becomes a sovereign country again where only its people, through a free vote, say who will govern". Chilean president Gabriel Boric and Uruguayan president Luis Lacalle Pou, who were some of the summit attendees, disapproved of Lula's comments.
Receptors of a particular type are linked to specific cellular biochemical pathways that correspond to the signal. While numerous receptors are found in most cells, each receptor will only bind with ligands of a particular structure. This has been analogously compared to how locks will only accept specifically shaped keys. When a ligand binds to a corresponding receptor, it activates or inhibits the receptor's associated biochemical pathway, which may also be highly specialised. Receptor proteins can be also classified by the property of the ligands. Such classifications include chemoreceptors, mechanoreceptors, gravitropic receptors, photoreceptors, magnetoreceptors and gasoreceptors.
A number of experiments have found that decay rates of other modes of artificial and naturally occurring radioisotopes are, to a high degree of precision, unaffected by external conditions such as temperature, pressure, the chemical environment, and electric, magnetic, or gravitational fields. Comparison of laboratory experiments over the last century, studies of the Oklo natural nuclear reactor (which exemplified the effects of thermal neutrons on nuclear decay), and astrophysical observations of the luminosity decays of distant supernovae (which occurred far away so the light has taken a great deal of time to reach us), for example, strongly indicate that unperturbed decay rates have been constant (at least to within the limitations of small experimental errors) as a function of time as well. Recent results suggest the possibility that decay rates might have a weak dependence on environmental factors. It has been suggested that measurements of decay rates of silicon-32, manganese-54, and radium-226 exhibit small seasonal variations (of the order of 0.1%). However, such measurements are highly susceptible to systematic errors, and a subsequent paper has found no evidence for such correlations in seven other isotopes (22Na, 44Ti, 108Ag, 121Sn, 133Ba, 241Am, 238Pu), and sets upper limits on the size of any such effects.
=== Long term exposure of residents living near medical supply warehouses === Residents living near Cardinal Health's warehouse, which holds sterilized medical supplies, in El Paso Texas reported respiratory symptoms in 2021. Some sources estimate these large warehouses holding sterilized medical equipment outgas more ethylene oxide than some sterilization plants due to laxer regulations. Further investigation discovered people living near these warehouses are being exposed to ethylene oxide levels sufficient to increase cancer risk to more than 1 in 10,000.
Sources: en.wikipedia.org
=== Labeling requirements === For US food and dietary supplement labeling purposes, the amount in a serving is expressed as a percent of Daily Value (%DV). For pantothenic acid labeling purposes, 100% of the Daily Value was 10 mg, but as of May 2016 it was revised to 5 mg to bring it into agreement with the AI. Compliance with the updated labeling regulations was required by January 2020 for manufacturers with US$10 million or more in annual food sales, and by January 2021 for manufacturers with lower volume food sales. A table of the old and new adult daily values is provided at Reference Daily Intake.
As a result of protests by Akwesasne residents on their rights to cross the border unimpeded, as provided under the 1795 Jay Treaty, the Canada Border Services Agency closed its post on Cornwall Island, instead requiring travellers to proceed to the checkpoint in the city of Cornwall. As a consequence of the arrangement, residents of the island are required to clear border controls when proceeding North to the Ontario mainland, as well as when proceeding South to Akwesasne territory in New York, thereby constituting internal controls from both a Canadian and an Akwesasne perspective. Similarly, travelling between Canada and the Quebec portion of the Akwesasne nation requires driving through the state of New York, meaning individuals must clear American controls when leaving Quebec proper and Canadian border controls when entering Quebec proper. However, Canada does not impose border controls when entering the Quebec portion of the Akwesasne Nation. Nevertheless, for residents who assert a Haudenosaunee national identity distinct from Canadian or American citizenship, the intricate network of Canadian and American border controls is seen as a foreign-imposed system of internal border controls, similar to the Israeli checkpoints in Palestinian territory. The city of Hyder, Alaska, has also been subject to internal border controls since America chose to stop regulating arrivals in Hyder from British Columbia.
phosphate Any chemical species or functional group derived from phosphoric acid (H3PO4) by the removal of one or more protons (H+); the completely ionized form, [PO4]3−, consists of a single, central phosphorus atom covalently bonded to four oxygen atoms via three single bonds and one double bond. Phosphates are abundant and ubiquitous in biological systems, where they occur either as free anions in solution, known as inorganic phosphates and symbolized Pi, or bonded to organic molecules via ester bonds. The huge diversity of organophosphate compounds includes all nucleotides, whose phosphate groups are linked by phosphodiester bonds to form the structural backbones of long nucleotide chains such as DNA and RNA, and the high-energy diphosphate and triphosphate substituents of individual nucleotides such as ADP and ATP serve as essential energy carriers in all cells. Phospholipids are major components of most membranes. Enzymes known as kinases and phosphatases catalyze the addition and removal of phosphate groups to and from these and other biomolecules.
=== Importance of resistivity === In an imperfectly conducting fluid, the magnetic field can generally move through the fluid according to a diffusion law, with the resistivity of the plasma serving as a diffusion constant. This means that solutions to the ideal MHD equations are applicable only for a limited time within a region of a given size before diffusion becomes too significant to ignore. One can estimate the diffusion time across a solar active region (from collisional resistivity) to be hundreds to thousands of years, much longer than the actual lifetime of a sunspot, so it would seem reasonable to ignore the resistivity. By contrast, a meter-sized volume of seawater has a magnetic diffusion time measured in milliseconds. Even in physical systems that are large and conductive enough that simple estimates of the Lundquist number suggest that the resistivity can be ignored, resistivity may still be important: many instabilities can increase the effective resistivity of the plasma by factors greater than 109. The enhanced resistivity is usually the result of the formation of small-scale structures such as current sheets or fine-scale magnetic turbulence, introducing small spatial scales into the system over which ideal MHD breaks down and magnetic diffusion can occur rapidly. When this happens, magnetic reconnection may occur in the plasma, releasing stored magnetic energy as waves, bulk mechanical acceleration of material, particle acceleration, and heat.
Sources: en.wikipedia.org
It is a synthetic peptide analogue of growth hormone-releasing hormone. Four substitutions in its sequence make it more resistant to enzymatic degradation than the natural hormone. In the version carrying a drug affinity complex, the peptide binds albumin and remains in circulation for days.
No regulatory agency has approved CJC-1295 for clinical use. Human trials were conducted in the 2000s, but the development programme was discontinued before any marketing application succeeded. Material sold today is offered as a research chemical, and its purity depends on the supplier.
Sermorelin is an unmodified fragment of growth hormone-releasing hormone and is cleared quickly. CJC-1295 contains substitutions that resist breakdown, and the form with a drug affinity complex persists much longer. Both act at the same receptor but differ substantially in duration of action.
The two share the same 29-amino-acid backbone. CJC-1295 carries an additional albumin-binding moiety that markedly extends its residence time in circulation, while the form without that moiety clears faster. Literature sometimes applies the name loosely to either variant.