This is a working overview of MOD GRF(1-29), written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-07-12. Anything still debated is marked as such rather than presented as settled.
The two variants differ dramatically in how long they persist in circulation. The form lacking the albumin-binding group has a plasma half-life measured in tens of minutes, comparable to the natural hormone fragment. The version carrying the drug affinity complex binds albumin and shows a half-life of roughly six to eight days in human studies. That figure comes from small trials that tracked hormone levels over extended periods. The physiological consequences of sustained versus pulsatile stimulation are still debated and the literature does not settle the point.
Lyophilized peptide powder is comparatively stable when kept dry, cold, and protected from light. Once dissolved, the molecule is vulnerable to deamidation, oxidation, and aggregation, with the rate depending on pH, buffer composition, and temperature. Alkaline conditions and repeated freeze-thaw cycles accelerate loss of the intact peptide. The methionine present in the native sequence is a known oxidation site, which is one reason it was replaced in the modified fragment. Suppliers typically recommend cold storage of solutions and use within a short window.
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.
At the pituitary, the peptide binds the growth hormone-releasing hormone receptor on somatotroph cells. Receptor activation raises intracellular cyclic AMP and triggers release of stored growth hormone. Somatostatin and other hypothalamic signals modulate this response. Negative feedback from insulin-like growth factor 1 also influences output. The same regulatory architecture operates with the native hormone. Whether the synthetic analog alters feedback dynamics over repeated exposure remains an open question. Most published receptor work uses cell models rather than intact human systems.
| Property | Value | Notes |
|---|---|---|
| Molecular mass | Approximately 3.4 to 3.6 kDa | Depends on whether the affinity complex is attached |
| Appearance | White to off-white lyophilized powder | Freeze-dried solid, often in a sealed vial |
| Solubility | Soluble in water and aqueous buffers | Dissolution rate varies with pH and buffer salt |
| Typical storage | Below minus 20 degrees Celsius, dry and dark | Dissolved material is usually kept cold and used promptly |
| Common analytical methods | Reversed-phase HPLC and mass spectrometry | Peptide mapping and amino acid analysis add sequence detail |
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.
The attached maleimide group explains the unusual duration of the DAC version. After injection it reacts with the thiol of cysteine-34 on serum albumin, forming a stable covalent bond. The resulting conjugate is too large for rapid kidney filtration and is shielded from many peptidases. Reported half-lives for this form reach several days, whereas the version without the group is cleared in roughly half an hour. That gap is the main pharmacological difference between the two.
Downstream of growth hormone, the liver and other tissues increase production of insulin-like growth factor 1, a mediator of many growth-promoting effects. Studies have documented elevated levels of both hormones after dosing, and the rise from the long-acting form persists longer than that produced by shorter-acting analogues. What remains unclear is whether sustained elevation of these markers translates into meaningful clinical benefit, and whether prolonged exposure carries risks that short trials could not detect.
CJC-1295 acts at the growth hormone-releasing hormone receptor, a G-protein-coupled receptor found on somatotroph cells in the anterior pituitary. Binding triggers a rise in cyclic AMP and calcium entry, which promotes release of stored growth hormone. Because the peptide mimics the body's own releasing hormone, it amplifies existing secretory pulses rather than driving continuous output. The size of the response therefore depends partly on the subject's own hormonal rhythm and feedback state.
In November 1979, the federal government informed the Bundestag that the West German public broadcasters ARD and ZDF had agreed to refuse to use the initialism. The ISO 3166-1 alpha-2 country code of West Germany was DE (for Deutschland, Germany), which has remained the country code of Germany after reunification. ISO 3166-1 alpha-2 codes are the most widely used country codes, and the DE code is notably used as a country identifier, extending the postal code and as the Internet's country code top-level domain .de. The less widely used ISO 3166-1 alpha-3 country code of West Germany was DEU, which has remained the country code of reunified Germany. The now deleted codes for East Germany, on the other hand, were DD in ISO 3166-1 alpha-2 and DDR in ISO 3166-1 alpha-3. The colloquial term West Germany or its equivalent was used in many languages. Westdeutschland was also a widespread colloquial form used in German-speaking countries, usually without political overtones.
==== MeSH D12.776.210.500.600 – myosins ==== MeSH D12.776.210.500.600.100 – myosin heavy chains MeSH D12.776.210.500.600.200 – myosin light chains MeSH D12.776.210.500.600.300 – myosin subfragments MeSH D12.776.210.500.600.465 – myosin type i MeSH D12.776.210.500.600.470 – myosin type ii MeSH D12.776.210.500.600.470.249 – cardiac myosins MeSH D12.776.210.500.600.470.249.249 – atrial myosins MeSH D12.776.210.500.600.470.249.500 – ventricular myosins MeSH D12.776.210.500.600.470.374 – nonmuscle myosin type iia MeSH D12.776.210.500.600.470.500 – nonmuscle myosin type iib MeSH D12.776.210.500.600.470.750 – skeletal muscle myosins MeSH D12.776.210.500.600.470.875 – smooth muscle myosins
A single dose of LSD (Definium Therapeutics's DT120 candidate) markedly reduced major depressive disorder symptoms versus placebo in a Phase 3 trial, with benefits lasting at least 12 weeks and no major safety concerns. LSD is a psychoplastogen, a compound capable of promoting rapid and sustained neural plasticity, an action that hypothetically might be involved in its therapeutic benefits. Preliminary evidence in humans suggests that a single dose of LSD may also temporarily benefit learning and memory. More research is needed to substantiate such notions. The British critical psychiatrist Joanna Moncrieff has critiqued the use and study of psychedelics like LSD for treatment of psychiatric disorders, highlighting concerns including excessive hype around these drugs, questionable biologically-based theories of benefit, blurred lines between medical and recreational use, flawed clinical trial findings, financial conflicts of interest, strong expectancy effects and large placebo responses, small and short-term benefits over placebo, and their potential for difficult experiences and adverse effects, among others.
Also in the 1930s Walter Reppe, an industrial chemist and later board member of BASF, discovered a number of homogeneous catalytic processes, such as the hydrocarboxylation, in which olefins or alkynes react with carbon monoxide and water to form products such as unsaturated acids and their derivatives. In these reactions, for example, nickel tetracarbonyl or cobalt carbonyls act as catalysts. Reppe also discovered the cyclotrimerization and tetramerization of acetylene and its derivatives to benzene and benzene derivatives with metal carbonyls as catalysts. BASF built in the 1960s a production facility for acrylic acid by the Reppe process, which was only superseded in 1996 by more modern methods based on the catalytic propylene oxidation.
Sources: en.wikipedia.org
On July 6, 2021, during the 2020 Summer Olympics, Brazil women's national volleyball team player Tandara was temporarily suspended for testing positive for enobosarm. The test was carried out and identified by the Brazilian Doping Control Authority (ABDC). On August 12, 2021, after the 2020 Summer Olympics, Chijindu "CJ" Ujah, A member of the silver medal-winning British 4×100 relay team was temporarily suspended for testing positive for both enobosarm and S-23. The sample was collected post event by the International Testing Agency (ITA) and confirmed two days later as positive. The case was referred to the anti-doping division of the Court of Arbitration for Sport. Finally in February 2022, Great Britain were stripped of their silver medal. In October 2022, Ujah was suspended for 22 months by the ITA. In October 2021, two Thoroughbred horses named Arafat and Komunist tested positive for enobosarm after races at Woodbine Racetrack. In a decision of the Alcohol and Gaming Commission of Ontario issued May 30, 2022, the horses were declared unplaced in the races in question, and their trainer Robert Gerl was fined $100,000 (as well as forfeiting prize money) and suspended from racing for 20 years. In May 2022, National Football League Wide receiver DeAndre Hopkins was suspended six games without pay by the NFL for violating the league's performance-enhancing drug policy. According to Hopkins, he tested positive for enobosarm.
=== Biological research === Researchers have explored the use of silver nanoparticles as carriers for delivering various payloads such as small drug molecules or large biomolecules to specific targets. Once the AgNP has had sufficient time to reach its target, release of the payload could potentially be triggered by an internal or external stimulus. The targeting and accumulation of nanoparticles may provide high payload concentrations at specific target sites and could minimize side effects.
=== Artificial satellite development === In 1955, with both the United States and the Soviet Union building ballistic missiles that could be used to launch objects into space, the stage was set for nationalistic competition. On July 29, 1955, James C. Hagerty, President Dwight D. Eisenhower's press secretary, announced that the United States intended to launch "small Earth circling satellites" between July 1, 1957, and December 31, 1958, as part of the US contribution to the International Geophysical Year (IGY). On August 2, at the Sixth Congress of the International Astronautical Federation in Copenhagen, scientist Leonid I. Sedov told international reporters at the Soviet embassy of his country's intention to launch a satellite as well, in the "near future".
Sources: en.wikipedia.org
There appear to be at least three distinct receptor complexes that amylin binds to with high affinity. All three complexes contain the calcitonin receptor at the core, plus one of three receptor activity-modifying proteins, RAMP1, RAMP2, or RAMP3.
=== Addiction and dependence liability === LSD is widely considered to be non-addictive, despite its potential for abuse. Attempts to train laboratory animals to self-administer LSD have been largely unsuccessful. Although tolerance to LSD builds up rapidly, a withdrawal syndrome does not appear, suggesting that a potential syndrome does not necessarily relate to the possibility of acquiring rapid tolerance to a substance. A report examining substance use disorder for DSM-IV noted that almost no hallucinogens produced dependence, unlike psychoactive drugs of other classes such as stimulants and depressants.
== Awards == Wennemers work was recognized by the Leonidas Zervas Award of the European Peptide Society (2010), the Pedler Award of the Royal Society of Chemistry (2016), the Inhoffen Medal (2017), the Netherlands Scholar Award for Supramolecular Chemistry (2019), the Arthur C. Cope Scholar Award of the American Chemical Society (2021), the Scoffone Prize of the Italian Peptide Society (2022), and the Vincent du Vigneaud Award of the American Peptide Society (2023). She also won ths 2020 Spark Award (invention) and the 2023 Golden Owl Award (teaching) from the ETH Zurich. Wennemers was awarded the Emil Fischer Medal by the German Chemical Society on September 7, 2026, for her pioneering work on synthetic peptides, becoming the first woman to win the award in its 114-year history.
Tianeptine/naloxone (developmental code names TNX-601, TNX-601-CR, TNX-601-ER), or naloxone/tianeptine, is an extended-release combination of tianeptine, an atypical μ-opioid receptor agonist, and naloxone, an orally inactive μ-opioid receptor antagonist, which was under development for the treatment of major depressive disorder, post-traumatic stress disorder (PTSD), and neurocognitive dysfunction associated with corticosteroid use but was never marketed. Whereas tianeptine is marketed widely throughout Europe, Asia, and Latin America but is not available in the United States or the United Kingdom, tianeptine/naloxone was under development for registration in the United States and other countries. In addition, whereas tianeptine has a short duration of action and requires administration three times per day, tianeptine/naloxone was developed as an extended-release formulation with enhanced pharmacokinetics suitable for once-daily administration. The combination formulation employs tianeptine as the oxalate salt, which is said to have improved physicochemical properties for use in the extended-release formulation compared to the amorphous tianeptine sodium that is used in immediate-release tianeptine-only formulations. Naloxone is used in misuse-resistant oral drug formulations as it is inactive if taken orally but becomes active if oral tablets are crushed and administered parenterally, such as by injection.
Sources: en.wikipedia.org
The version carrying the affinity complex bears a maleimide group that binds serum albumin, which extends its circulation time to several days. The version without it lacks this group and clears within roughly half an hour. The two are chemically related but behave very differently once in the body.
In common usage the name without the affinity complex is often equated with MOD GRF 1-29, a fragment carrying four stabilizing substitutions. Strictly speaking, the term originally referred to the albumin-binding version. The overlap in naming causes frequent ambiguity in both informal and technical writing.
Reversed-phase chromatography separates the peptide from related impurities and yields a purity estimate. Mass spectrometry confirms the molecular mass and detects modifications such as oxidation. Sequence-level checks rely on peptide mapping or amino acid analysis when stronger confirmation is needed.
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.