MOD 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.
Last reviewed on 2026-07-28. Where a claim depends on a specific study, the study is described rather than over-claimed.
CJC-1295 is a synthetic peptide belonging to the growth hormone-releasing hormone analog family. It comprises twenty-nine amino acid residues derived from the N-terminal region of natural GHRH. The molecule incorporates several non-natural substitutions that increase resistance to enzymatic degradation. These modifications extend its activity compared with the native hormone fragment. Researchers use it to study pituitary growth hormone secretion in laboratory and clinical settings. This compound is distinct from native GHRH in its stability profile.
Two principal forms appear in the literature and in research supply. One carries a drug affinity complex, a maleimide-based group that forms a covalent bond with circulating albumin. This linkage slows clearance and produces a long-lasting elevation of peptide levels. The other form lacks that group and is often labeled MOD GRF(1-29). It has a much shorter circulation time. Both variants retain the same core receptor-binding sequence. Reported half-lives differ substantially between the two.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular weight, DAC form | About 3647 Da | Varies with salt form |
| Molecular weight, non-DAC form | About 3358 Da | MOD GRF(1-29) |
| Solubility class | Water soluble | Also dissolves in polar solvents |
| Reported half-life, DAC form | About five to eight days | Values from human studies |
| Common synonyms | CJC-1295; MOD GRF(1-29) | Name depends on variant |
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.
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.
Batch-to-batch consistency depends on solid-phase peptide synthesis and subsequent purification. Coupling efficiency, resin choice, and cleavage conditions all affect the final profile. Counter-ion content and moisture can shift the apparent mass of a batch. Documentation typically includes a certificate of analysis with chromatograms and spectra. Independent verification by a second laboratory is sometimes requested. Whether a given certificate reflects the actual vial contents depends on chain of custody. Analytical methods themselves carry uncertainty that should be stated alongside results.
Lyophilized material is typically stored at minus twenty degrees Celsius or lower. Keeping the vial dry and protected from light preserves peptide integrity. Repeated freeze-thaw cycles can cause aggregation or loss of activity. Once dissolved, solutions are generally kept at two to eight degrees Celsius. Stability data for reconstituted solutions vary, and long-term behavior is not fully established. Working aliquots reduce the number of times a stock container is opened.
Dehydration at 315 °C: 2 NaHSO4 → Na2S2O7 + H2O Cracking at 460 °C: Na2S2O7 → Na2SO4 + SO3 The latter occurs at lower temperatures (around 300 °C) in the presence of catalytic H2SO4. KHSO4 undergoes the same reactions at a higher temperature. Another two step method involving a salt pyrolysis starts with concentrated sulfuric acid and anhydrous tin tetrachloride:
Serine proteases, including trypsin, chymotrypsin, and subtilisin Extracellular lipases, including pancreatic lipase, hepatic lipase, gastric lipase, endothelial lipase, and lipoprotein lipase Intracellular lipases, including hormone sensitive lipase, monoacylglycerol lipase, adipose triglyceride lipase, and diacylglycerol lipase Cholinesterases, including acetylcholinesterase and butyrylcholinesterase Small molecule thioesterases, including fatty acid synthase and the acyl-CoA thioesterases Some phospholipases, including phospholipase A2 and platelet activating factor acetylhydrolase Protein and glycan hydrolases, including protein phosphate methylesterase 1, acyloxyacyl hydrolase and sialic acid acetylesterase Some amidases, including fatty acid amide hydrolase Some peptidases, including dipeptidyl peptidase 4, fibroblast activation protein, and prolylendopeptidase
Maryanoff (born 1949), American organic/medicinal chemist Maud Menten (1879–1960), Canadian biochemist Helen Vaughn Michel (born 1932), American nuclear chemist Alexandra Navrotsky (born 1943), American geochemist Dorothy Virginia Nightingale (1902–2000), American organic chemist Yolanda Ortiz (chemist) (1924–2019), Argentine chemist, environmentalist Kathlyn Parker, American organic chemist Emma Parmee, British-born medicinal/organic chemist Marguerite Perey (1909–1975), French physicist, student of Marie Curie, discovered the element francium in 1939 Mary Engle Pennington (1872–1952), American food chemist Eva Philbin (1914–2005), Irish chemist Iphigenia Photaki (1921–1983), Greek organic chemist Darshan Ranganathan (1941–2001), Indian organic chemist Mildred Rebstock (1919–2011), American Pharmaceutical chemist Sibyl Martha Rock (1909–1981), American pioneer in mass spectrometry and computing Elizabeth Rona (1890–1981), Hungarian (naturalized American) nuclear chemist and polonium expert Mary Swartz Rose (1874–1941), Nutrition chemist Melanie Sanford (born 1975), American organic chemist Maxine L. Savitz, American Chemist Patsy Sherman (1930–2008), American chemist, co-inventor of Scotchgard Odette L.
== History == The earliest description of a lectin is believed to have been given by Peter Hermann Stillmark in his doctoral thesis presented in 1888 to the Imperial University of Dorpat. Stillmark isolated ricin, an extremely toxic hemagglutinin, from seeds of the castor plant (Ricinus communis). Although lectins were first discovered in plants, they are now known to be present throughout nature. The first lectin to be purified on a large scale and available on a commercial basis was concanavalin A, which is now the most-used lectin for characterization and purification of sugar-containing molecules and cellular structures. The legume lectins are probably the most well-studied lectins. Long before a deeper understanding of their numerous biological functions was developed, the plant lectins, also known as phytohemagglutinins, were noted for their particularly high specificity for foreign glycoconjugates (e.g., those of fungi and animals) and used in biomedicine for blood cell testing and in biochemistry for fractionation.
Sources: en.wikipedia.org
=== Growth and expansion === In 1997, Medtronic opened a production site for implantable pacemakers and brain pacemakers in Tolochenaz, Switzerland. One in five pacemakers implanted globally today is made here. The site is also used as a European training centre for doctors. In 1998, Medtronic acquired Physio-Control for $538 million. In 2014, Integra LifeSciences announced it was acquiring instrumentation lines from Medtronic for $60 million. The deal included Medtronic's MicroFrance and Xomed manual ear, nose and throat and laparoscopic surgical instruments, as well as a manufacturing facility in France. In February 2016, the company announced that it would acquire Bellco from private equity firm Charme Capital Partners. In June, the company announced its acquisition of HeartWare International Inc. for $1.1 billion. In December 2017, Medtronic acquired Crospon for €38 million (approximately $45 million). In September 2018, the company acquired Mazor Robotics for $1.64 billion ($58.50 per American Depository Share or $29.25 per ordinary share. In late November, Medtronic acquired Nutrino Health Ltd boosting the company's nutrition-related data services and analytics. In March 2017, Bloomberg's database of U.S. tax inversions listed Medtronic and Wright Medical Group (Medtronic's 2015 inversion to Ireland was over $100 billion, while Wright's 2015 inversion to the Netherlands was $3.3 billion) as the only U.S. tax inversions of a U.S. medical device company in history.
The initiating event in aortic dissection is a tear in the intimal lining of the aorta. Due to the high pressures in the aorta, blood enters the media at the point of the tear. The force of the blood entering the space between the intima and media layers causes the tear to extend. It may extend proximally (closer to the heart) or distally (away from the heart) or both. The blood travels through the space, creating a false lumen (the true lumen is the normal conduit of blood in the aorta). Separating the false lumen from the true lumen is a layer of intimal tissue known as the intimal flap. Two-thirds of aortic dissections involve the ascending aorta, the rest involve only the descending aorta (type B aortic dissections). While it is not always clear why an intimal tear may occur, quite often it involves degeneration of the collagen and elastin that make up the media. This is known as cystic medial necrosis and is most commonly associated with Marfan syndrome and is also associated with Ehlers–Danlos syndrome. In about 13% of aortic dissections, no evidence of an intimal tear is found. In these cases, the inciting event is thought to be an intramural hematoma (caused by bleeding within the media). Since no direct connection exists between the true lumen and the false lumen in these cases, diagnosing an aortic dissection by aortography is difficult if the cause is an intramural hematoma. An aortic dissection secondary to an intramural hematoma should be treated the same as one caused by an intimal tear.
=== Other complications === Compartment syndrome is treated with surgery to relieve the pressure inside the muscle compartment and reduce the risk of compression on blood vessels and nerves in that area. Fasciotomy is the incision of the affected compartment. Often, multiple incisions are made and left open until the swelling has reduced. At that point, the incisions are closed, often requiring debridement (removal of non-viable tissue) and skin grafting in the process. The need for fasciotomy may be decreased if mannitol is used, as it can relieve muscle swelling directly. Disseminated intravascular coagulation generally resolves when the underlying causes are treated, but supportive measures are often required. For instance, if the platelet count drops significantly and there is resultant bleeding, platelets may be administered.
In March 1924, having briefly considered the possibility of removing the offending article from the treaty, the government suspended any further negotiations; within six months they withdrew their support in favour of their central Arabian ally Ibn Saud, who proceeded to conquer Hussein's kingdom.
Plastocyanin is one of the family of blue copper proteins that are involved in electron transfer reactions. The copper-binding site is described as distorted trigonal pyramidal. The trigonal plane of the pyramidal base is composed of two nitrogen atoms (N1 and N2) from separate histidines and a sulfur (S1) from a cysteine. Sulfur (S2) from an axial methionine forms the apex. The distortion occurs in the bond lengths between the copper and sulfur ligands. The Cu−S1 contact is shorter (207 pm) than Cu−S2 (282 pm). The elongated Cu−S2 bonding destabilizes the Cu(II) form and increases the redox potential of the protein. The blue color (597 nm peak absorption) is due to the Cu−S1 bond where S(pπ) to Cu(dx2−y2) charge transfer occurs. In the reduced form of plastocyanin, His-87 will become protonated with a pKa of 4.4. Protonation prevents it acting as a ligand and the copper site geometry becomes trigonal planar.
Sources: en.wikipedia.org
It is a synthetic peptide modeled on growth hormone-releasing hormone. The molecule is used in research on pituitary growth hormone secretion. It differs from the natural hormone through several stabilizing substitutions.
The DAC form carries a maleimide group that binds albumin and extends circulation time. The non-DAC form lacks this group and clears much faster. Both share the same receptor-binding core.
It targets the growth hormone-releasing hormone receptor on pituitary somatotroph cells. Activation raises cyclic AMP and promotes growth hormone release. Normal feedback pathways remain part of the response.
Mass spectrometry establishes whether the observed molecular weight matches the calculated sequence mass. Chromatographic retention and fragment mapping add further confidence about sequence and composition. A single technique alone is rarely treated as sufficient evidence of identity.