lyophilized powder 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 2026-01-20. Numbers and descriptions here follow the published literature rather than marketing material.
CJC-1295 is a synthetic peptide designed to mimic growth hormone-releasing hormone (GHRH), the endogenous signal that prompts the pituitary gland to release growth hormone. The compound is a modified fragment of the natural hormone, spanning the first twenty-nine amino acids of GHRH with several substitutions that slow enzymatic breakdown. Two variants circulate in research settings: one carrying a drug affinity complex (DAC) and one without it. The DAC-free form is frequently labelled Mod GRF(1-29) in catalogs and discussion forums.
The peptide binds GHRH receptors on somatotroph cells within the anterior pituitary, triggering a signalling cascade that increases growth hormone secretion. Its improved resistance to dipeptidyl peptidase IV degradation distinguishes it from the parent hormone. In the DAC-bearing version, a maleimide group reacts with a cysteine residue on serum albumin, forming a covalent bond that keeps the peptide in circulation far longer. That albumin attachment is the central design feature separating the two research variants.
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.
Laboratory handling centers on minimizing exposure to water, heat and oxygen before use. Working solutions are typically prepared in sterile water or a mild buffer, and any residual particulate matter is removed by filtration. When the powder dissolves slowly, a small proportion of acetonitrile or dilute acetic acid is sometimes added as a co-solvent. Containers are kept sealed and desiccated between uses. Records of lot number, reconstitution date and storage conditions support later comparison of results across experiments.
| Property | Value | Notes |
|---|---|---|
| Molecular weight (with DAC) | ~3647 Da | Calculated from the full amino acid sequence |
| Molecular weight (without DAC) | ~3368 Da | Mod GRF(1-29) variant |
| Appearance | White lyophilized powder | Typical form supplied for research |
| Solubility | Soluble in water | Dissolves in aqueous buffers |
| Receptor target | GHRH receptor | Expressed on pituitary somatotroph cells |
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.
The compound emerged from work at a Canadian biotechnology firm in the early 2000s. Early human studies examined its effect on growth hormone and insulin-like growth factor 1 in healthy volunteers and in people with HIV-associated fat redistribution. Reports described sustained increases in both markers after a single injection. Development did not advance to regulatory approval, and the clinical programme was later discontinued. The molecule is now encountered mainly as a research chemical rather than a marketed medicine.
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.
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.
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.
It was found that Cu2+ was critically needed for PDTC induced apoptosis in HL-60 cells. The copper complex of salicylaldehyde benzoylhydrazone (SBH) derivatives showed increased efficacy of growth inhibition in several cancer cell lines, when compared with the metal-free SBHs. SBHs can react with many kinds of transition metal cations and thereby forming a number of complexes. Copper-SBH complexes were more cytotoxic than complexes of other transitional metals (Cu > Ni > Zn = Mn > Fe = Cr > Co) in MOLT-4 cells, an established human T-cell leukemia cell line. SBHs, especially their copper complexes appeared to be potent inhibitors of DNA synthesis and cell growth in several human cancer cell lines, and rodent cancer cell lines. Salicylaldehyde pyrazole hydrazone (SPH) derivatives were found to inhibit the growth of A549 lung carcinoma cells. SPH has identical ligands for Cu2+ as SBH. The Cu-SPH complex was found to induce apoptosis in A549, H322 and H1299 lung cancer cells.
"It really got to them," recalls Dr. William Schneider Jr., [former] undersecretary of state for military assistance and technology, who saw classified "after-action reports" that indicated U.S. flight activity. "They didn't know what it all meant. A squadron would fly straight at Soviet airspace, and other radars would light up and units would go on alert. Then at the last minute the squadron would peel off and return home." From the accounts of CIA and senior KGB officers, by May 1981, obsessed with historical parallels with the 1941 German invasion and Reaganite rhetoric, and with no defensive capability against the Pershing IIs, Soviet leaders believed the United States was preparing a secret nuclear attack on the USSR and initiated Operation RYaN. Under this, agents abroad monitored service and technical personnel who would implement a nuclear attack so as to be able either to preempt it or have mutually assured destruction. On 1 September 1983, the Soviet military shot down a South Korean passenger jet, Korean Air Lines Flight 007, that had strayed into Soviet airspace. All 269 people aboard the aircraft were killed, including U.S. Representative Larry McDonald and many other Americans. The first Pershing II missiles were delivered to West Germany on 1 December 1983. Bruce G. Blair, an expert on Cold War nuclear strategies and former president of the World Security Institute in Washington, D.C., says the American–Soviet relationship at that time:
=== Fertilizers === Metal chelate compounds are common components of fertilizers to provide micronutrients. These micronutrients (manganese, iron, zinc, copper) are required for the health of the plants. Most fertilizers contain phosphate salts that, in the absence of chelating agents, typically convert these metal ions into insoluble solids that are of no nutritional value to the plants. EDTA is the typical chelating agent that keeps these metal ions in a soluble form.
==== Anti-Jo-1 ==== Although anti-Jo-1 antibodies are often included with ANAs, they are actually antibodies to the cytoplasmic protein, Histidyl-tRNA synthetase – an aminoacyl-tRNA synthetase essential for the synthesis of histidine loaded tRNA. They are highly associated with polymyositis and dermatomyositis, and are rarely found in other connective tissue diseases. Around 20–40% of polymyositis is positive for Jo-1 antibodies and most will have interstitial lung disease, HLA-DR3 and HLA-DRw52 human leukocyte antigen (HLA) markers; collectively known as Jo-1 syndrome.
Sources: en.wikipedia.org
=== Frederick Banting and the discovery of insulin === At the end of 1920, Macleod was approached by Frederick Banting, a young Canadian physician who had the idea of curing diabetes using an extract from a pancreas whose functioning had been disrupted. Macleod was not enthusiastic, because (unlike Banting) he knew about unsuccessful experiments in this direction by other researchers. He thought it more likely that the nervous system had a crucial role in regulating blood glucose concentration. Even though Banting had virtually no experience of physiology, he managed to convince Macleod to lend him laboratory space during a holiday in Scotland that summer. In addition to the laboratory, Macleod provided experimental animals and his student Charles Best, who worked as a demonstrator. Macleod also advised on project planning and the use of analytical techniques, and assisted with the operation on the first dog. While Macleod was away, Banting and Best achieved a breakthrough: they isolated an internal secretion of the pancreas and succeeded in reducing the blood sugar level of another dog, whose pancreas had been surgically removed.
But it did get a little close there for a while. As you may know, there were 61 planes in the air headed toward Haïti at the time they finally agreed. And at one point General Biamby came in and told General Cédras that he had just gotten word on his telephone that the airplanes had taken off from Pope Air Force Base, with soldiers from Fort Bragg, and that both disconcerted them and caused them to be suspicious of the intent of the negotiations, but it also created a situation where immediately after that, the key points they had been refusing to agree to were agreed to, a date certain, other matters that I won't go into in detail here.
At the beginning of Hong Kong's opening up, Western medicine was not yet popular, and Western medicine doctors were mostly foreigners; local residents mostly relied on Chinese medicine practitioners. In 1841, the British government of Hong Kong issued an announcement pledging to govern Hong Kong residents in accordance with all the original rituals, customs and private legal property rights. As traditional Chinese medicine had always been used in China, the use of traditional Chinese medicine was not regulated. The establishment in 1870 of the Tung Wah Hospital was the first use of Chinese medicine for the treatment in Chinese hospitals providing free medical services. As the promotion of Western medicine by the British government started from 1940, Western medicine started being popular among Hong Kong population. In 1959, Hong Kong had researched the use of traditional Chinese medicine to replace Western medicine.
Sources: en.wikipedia.org
The synthetic peptide keeps the receptor-binding region of GHRH but carries substitutions that resist enzymatic cleavage. In the DAC version, an added group also anchors the molecule to albumin, extending its presence in the bloodstream.
The maleimide group forms a covalent link with albumin, an abundant blood protein. This attachment slows clearance, so a single administration persists much longer than the unmodified peptide. The feature is the main reason the two variants are handled differently in study design.
It is not an approved therapeutic product in major regulatory jurisdictions. It appears in research chemical catalogs and scientific literature rather than pharmacy shelves. Clinical development was limited and did not reach approval.
The mass difference from the linker is large enough for routine detection by mass spectrometry. The unconjugated form gives a single sharp signal at its expected weight. Material that has already reacted with albumin shows a much higher mass and a broadened chromatographic peak.