If you have been reading about reverse-phase HPLC and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-01-22. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
Analytical confirmation usually relies on reversed-phase high-performance liquid chromatography for purity and on liquid chromatography coupled to mass spectrometry for identity. Mass data reveal the expected molecular mass and can flag truncated or oxidized species. Amino acid analysis and peptide mapping provide sequence-level verification. Immunoassays are used in some biological matrices, but antibodies raised against one releasing-hormone analog may cross-react with another. Reported purity figures depend heavily on the method used, so comparisons between suppliers require matching the analytical approach.
| 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 |
CJC-1295 is a synthetic peptide modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. Its sequence corresponds to the first twenty-nine residues of human GHRH, with four substitutions that slow enzymatic breakdown. Early descriptions placed the compound in research on growth hormone deficiency and related conditions, and later literature groups it with the long-acting GHRH analogs. The name appears in both laboratory and popular fitness writing, where it sometimes labels chemically different peptides.
Two related peptides circulate under the CJC-1295 label, and they differ mainly in how long they persist in circulation. The version carrying a drug affinity complex includes a maleimidopropionic acid linker that forms a covalent bond with serum albumin. The other version, usually written as modified GRF(1-29) or tetrasubstituted GRF(1-29), lacks that linker and is cleared quickly. Mixing the two produces inconsistent readings of published half-life values, because the linker rather than the receptor-facing sequence drives most of the difference.
The core sequence keeps the receptor-binding region of GHRH while replacing four positions that are vulnerable to dipeptidyl peptidase-4 and other proteases. Substitutions at positions 2, 8, 15, and 27 raise metabolic stability relative to the natural hormone. The N-terminal residues remain essential for activity, so changes there generally lower potency. Molecular weight sits near 3368 daltons for the tetrasubstituted analog without the linker, while the albumin-binding form is heavier because of the added maleimide group.
Reverse-phase high-performance liquid chromatography is the standard tool for purity assessment. The technique separates the target peptide from truncated or modified byproducts. Mass spectrometry confirms molecular weight and supports sequence verification. Electrospray ionization and matrix-assisted laser desorption are both used. Amino acid analysis provides an independent check on composition. Purity values are commonly reported as area percentage from the chromatogram. Residual trifluoroacetate and water content are also measured in many quality programs.
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.
This tantra contains a passage which appears to suggest that "the first ten terms of dependent origination are prenatal." He also notes that there is a tantric interpretation of dependent origination in the Guhyasamājatantra, "in which the first three members are equivalent to three mystical light stages.
=== Autoimmunity treatment === Acting as DAMPs, HSPs can extracellularly promote autoimmune reactions leading to diseases as rheumatoid arthritis or systemic lupus erythematosus. Nevertheless, it was found, that application of some HSPs into patients is able to induce immune tolerance and treat autoimmune diseases. The underlying mechanism is not known. HSPs (especially hsp60 and hsp70) are used in clinical studies to treat rheumatoid arthritis and type 1 diabetes. Current therapeutic research areas in the treatment for DM include: long-term physical exercise, hot tub therapy (HTT), and alfalfa-derived HSP70 (aHSP70). Hsp90 inhibitors are another possible treatment for autoimmunity, because hsp90 is necessary for proper folding of many pro-inflammatory proteins (components of PI3K, MAPK and NF-kB cascades).
It can occur as a result of a pre-existing infection or one acquired during pregnancy. Iatrogenic transmission, due to medical procedures such as injection or transplantation of infected material. Vector-borne transmission, transmitted by a vector, which is an organism that does not cause disease itself but that transmits infection by conveying pathogens from one host to another. The relationship between virulence versus transmissibility is complex; with studies showing no clear relationships between the two. There is still a small number of evidence that partially suggests a link between virulence and transmissibility.
He also said two border settlements were shelled by Ukraine, injuring four. The Russian Interior Ministry placed two former Ukrainian defence ministers and a former commander of the Armed Forces of Ukraine to its wanted list. The Wagner Group's Yevgeny Prigozhin said he had asked prosecutors to investigate whether senior Russian defense officials had committed any "crime" before or during the war in Ukraine, without providing specific details. Germany ordered the closure of four out of five Russian consulates in the country, in retaliation for the expulsion of German diplomatic staff from Russia and the closure of the German consulates in Kaliningrad, Yekaterinburg and Novosibirsk. Ukrainian Prime Minister Denys Shmyhal said the country received $1.25 billion from the United States as a part of the World Bank’s Public Expenditures for Administrative Capacity Endurance (PEACE) project, saying that the funds would "be used to support the state budget, especially for social and humanitarian spending." The Pentagon announced an additional $300-million aid package to help bolster Ukrainian air defenses, particularly additional munitions for Patriot air defense systems.
Sources: en.wikipedia.org
== Analogs == Structural analogs of desmethylprodine with different N-substituents than a methyl group on the piperidine have been investigated. Several of these have significantly greater in vitro potency compared to desmethylprodine.
=== Other formulations === The original oral formulation of selegiline was developed for the treatment of depression. However, it ended up being developed and approved for the treatment of Parkinson's disease instead. In any case, oral selegiline has been widely used off-label to treat depression. The transdermal patch form of selegiline was developed and approved specifically for the treatment of depression. It was also under development for the treatment of Alzheimer's disease, attention deficit hyperactivity disorder (ADHD), cognition disorders, and Parkinson's disease, but development for these indications was discontinued. The ODT form of selegiline was developed and licensed exclusively for the treatment of Parkinson's disease.
5 December – A single mutation known as Q226L is found to enhance the ability of H5N1 ('bird flu') to infect human cells, particularly in the respiratory tract. Previously, at least three mutations were thought to be required for the virus to infect people and spread between them. 7 December – A study in The Lancet finds that life expectancy progress in the United States is slowing. Only modest increases are likely by 2050, as the country falls below nearly all high-income and some middle-income countries in the global rankings. 9 December – Astronomers report using the infrared capabilities of the James Webb Space Telescope to find 100 of the smallest asteroids ever detected in the main belt, some measuring just 10 metres in diameter. 10 December – AI-based transfer learning predicts that global warming will reach 3°C faster than previously expected. 13 December – A new light-induced gene therapy using nanoparticles to target the mitochondria of cancer cells is demonstrated. 16 December – The China Aerospace Science and Technology Corporation (CASC) launches the first batch of the Guowang (Xingwang) megaconstellation, a planned constellation of 13,000 satellites using a Long March 5 rocket at the Wenchang Space Launch Site. 17 December – Zhúlóng ("Torch Dragon"), discovered by the James Webb Space Telescope, is reported as being the most distant known spiral galaxy ever found, seen as it appeared just 1.1 billion years after the Big Bang.
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 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.