GRF(1-29) raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2025-08-28 and is reviewed periodically as new material appears.
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.
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.
Reconstitution is typically performed with sterile water or bacteriostatic water, added slowly against the vial wall. The resulting solution should be clear and colorless; cloudiness or visible particles suggest a problem with the material or the diluent. Once in solution, the peptide is less stable than the dry powder. Refrigerated storage at two to eight degrees Celsius is common for short-term holding, while freezing aliquots is described for longer periods.
Purity is most often assessed by reversed-phase high-performance liquid chromatography, reported as a percentage of total peak area. Identity is confirmed by mass spectrometry, which yields a molecular ion consistent with the expected sequence. Amino acid analysis and peptide mapping provide additional characterization. Reported purity values are method-dependent, so figures from different laboratories are not always directly comparable without details of column, gradient, and detection wavelength.
Peptide degradation proceeds mainly through hydrolysis, oxidation of methionine, and deamidation of asparagine or glutamine residues. The maleimide group on the albumin-binding variant can also react with thiols or hydrolyze in aqueous media. Because these pathways accelerate with temperature and pH extremes, handling conditions strongly influence measured stability. Stability data in the public literature are limited and often generated under differing conditions, so general statements about shelf life should be read as approximate.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic peptide | Analog of growth hormone-releasing hormone |
| Chain length | 29 amino acids | Based on the GRF(1-29) fragment |
| Appearance | White to off-white lyophilized powder | Common research supply form |
| Solubility | Soluble in water and aqueous buffers | Powder requires reconstitution before use |
| Typical storage | −20 °C or below | Kept away from light and moisture |
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.
Characterization of this peptide relies on a small set of routine techniques. Reversed-phase high-performance liquid chromatography separates the target from truncated or oxidized by-products and yields a purity estimate when paired with ultraviolet detection near 214 nanometers. Mass spectrometry, either electrospray coupled to liquid chromatography or matrix-assisted laser desorption, confirms that the observed mass matches the value calculated for the expected sequence. Amino acid analysis, and enzymatic digestion followed by fragment mapping, are used when the sequence itself rather than the mass requires verification.
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.
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.
Identity and purity are established with reversed phase high performance liquid chromatography coupled to mass spectrometry. The chromatographic step separates the target peptide from truncated sequences and deletion products, while the mass measurement confirms the expected molecular weight to within a fraction of a dalton. Because the two common variants differ by the presence of the linker, mass alone can distinguish them in the unconjugated state. Amino acid analysis and peptide mapping are used when sequence level confirmation is required.
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.
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.
=== Glassware === Silanization (or siliconization) of glassware is a common application that increases the hydrophobicity of a glass container. Thus treated, the glassware produces a flat meniscus and allowing for more complete transfer of aqueous solutions. Silanization of glassware is used in cell culturing to minimize adherence of cells to flask walls. Additionally, the silanization process is also used in biomedical fields for a wide variety of purposes, including anchoring DNA to substrates. Silanization of glassware can be achieved by dipping into a solution of 5-10% dimethyldiethoxysilane followed by heating. Silanization is also used for DNA chips. Nucleic acids do not bond to untreated glass surfaces. Silanization can be providing a better bonding site for the nucleic acids onto the chip. A common silane used to treat glass surfaces for this application is (3-mercaptopropyl)trimethoxysilane, which increases the number of reactive thiol groups on the surface The nucleic acids can bond to these available thiol groups on the surface of the glass DNA chip after silanization occurs.
AAS are frequently produced in pharmaceutical laboratories, but, in nations where stricter laws are present, they are also produced in small home-made underground laboratories, usually from raw substances imported from abroad. In these countries, the majority of steroids are obtained illegally through black market trade. These steroids are usually manufactured in other countries, and therefore must be smuggled across international borders. As with most significant smuggling operations, organized crime is involved. In the late 2000s, the worldwide trade in illicit AAS increased significantly, and authorities announced record captures on three continents. In 2006, Finnish authorities announced a record seizure of 11.8 million AAS tablets. A year later, the DEA seized 11.4 million units of AAS in the largest U.S. seizure ever. In the first three months of 2008, Australian customs reported a record 300 seizures of AAS shipments. In the U.S., Canada, and Europe, illegal steroids are sometimes purchased just as any other illegal drug, through dealers who are able to obtain the drugs from a number of sources. Illegal AAS are sometimes sold at gyms and competitions, and through the mail, but may also be obtained through pharmacists, veterinarians, and physicians. In addition, a significant number of counterfeit products are sold as AAS, in particular via mail order from websites posing as overseas pharmacies. In the U.S., black-market importation continues from Mexico, Thailand, and other countries where steroids are more easily available, as they are legal.
== Recognition == 1989 – Award of the Mass Spectrometry Society of Japan 2002 – Nobel Prize in Chemistry 2002 – Order of Culture 2002 – Person of Cultural Merit 2002 – Honorary doctorate from Tohoku University 2003 – Honorary citizenship of Toyama Prefecture 2003 – Special Award of the Mass Spectrometry Society of Japan 2006 – Member of Japan Academy 2024 – IEEE Milestone for "LAMS-50K" (one of the 5-member development team)
Omeprazole was first made in 1979 by Swedish AB Hässle, part of Astra AB. It was the first of the proton pump inhibitors (PPI). Astra AB, now AstraZeneca, launched it as an ulcer medicine under the name Losec in Sweden. It was first sold in the United States in 1989 under the brand name Losec. In 1990, at the request of the US Food and Drug Administration, the brand name Losec was changed to Prilosec to avoid confusion with the diuretic Lasix (furosemide). The new name led to confusion between omeprazole (Prilosec) and fluoxetine (Prozac), an antidepressant. Prilosec is owned by Procter & Gamble in alliance with AstraZeneca and the product is designed to address frequent heartburn, which can be triggered by various factors such as certain foods, stress, and smoking. Prilosec was first introduced in 1989 as a prescription medication approved by the FDA for the treatment of severe heartburn. In 2003, Prilosec OTC was launched as the first over-the-counter option for managing frequent heartburn. It is known for its advertising campaign featuring Larry the Cable Guy as the spokesperson for the brand, during the 2010s, emphasizing the concept of "Zero Heartburn".
10 December – Foreign Secretary David Cameron threatens to withdraw co-operation with Scottish ministers following a meeting between Humza Yousaf, the First Minister of Scotland, and Turkish President Recep Tayyip Erdogan at the 2023 United Nations Climate Change Conference, which took place without the presence of a UK official and was consequently a breach of protocol. In response, Yousaf calls the threat "petty" and "misguided". 11 December – New modernised trains are introduced on the Glasgow Subway as part of a £288m upgrade of the city's underground rail system. The Foreign and Commonwealth Office is to move from its Abercrombie House offices in East Kilbride to an undisclosed location in Glasgow some time after 2025, it is announced, with His Majesty's Revenue and Customs moving from Queensway House to replace the FCO at Abercrombie House. 12 December – Five men are charged in connection with historic sexual abuse at Edinburgh Academy. Perth and Kinross Council provisionally approves a 100% increase in Council Tax on second homes. 13 December – Nuns Sister Sarah McDermott, 79, and Sister Eileen Igoe, 79, and carer Margaret Hughes, 76, are convicted of mistreating children at Smyllum Park, an orphanage in Lanark, from 1969 until its closure in 1981. 14 December – Robert O'Brien, aged 45, Andrew Kelly, 44, and Donna Marie Brand, also aged 44, are convicted of the 1996 murder of Caroline Glachan following a trial at the High Court in Glasgow. All three were teenagers at the time the crime was committed.
Sources: en.wikipedia.org
=== Computing === C4 (conference), a Macintosh software developers conference C4 Engine, a next-generation 3D game engine C4 model, a graphical notation technique for diagramming software architecture Cx4 chip, an add-on microprocessor chip employed by certain Super NES game cartridges (often incorrectly referred to as the C4 chip) Controlled collapse chip connection or flip chip, a method for interconnecting semiconductor devices VIA C4, a planned design of central processing unit for a personal computer
I am so relieved. I can't even believe it. Exactly two years ago I was forced to have as much security as possible due to threats. Ever since then, i have never walked alone in the streets. It was heavy. Fortunately, I could still do my job. It was a difficult time in my career. When you hear such news, it is an incredible relief. In 2017, writer Raf Sauviller published his book Borgerokko Maffia, which was distributed to many libraries across Flanders (Belgium) and the Netherlands. In his book, he discusses the corruption that takes place in the Port of Antwerp amongst police officers and Customs controls. According to research which was carried out in 2018, the municipality of Borgerhout, Antwerp, had an illegal economy which was larger than the regular economy due to the influx of funds by the Moroccan mafia. During an interview by the newspaper De Morgen on the context of this book, the mayor of Antwerp, Bart De Wever, admitted that there were many difficulties on intercepting the main commanders of the Moroccan mafia in Antwerp. He also stated:
== Career == In 2004, Friedler joined the Institute of Chemistry at the Hebrew University of Jerusalem as a senior lecturer. He became an associate professor with tenure in 2009 and was appointed full professor in 2015. From 2005 to 2009, he headed the university's undergraduate chemistry–biology programme. He was head of the School of Chemistry. Friedler served as vice rector of the Hebrew University from 2016 to 2020. During the same period, he chaired the university's central student admissions committee. He was dean of its Faculty of Science from 2020 to 2024. He chaired the Hebrew University for the Youth from 2019 to 2024. In October 2024, Friedler became director and chief executive officer of SHARE, the Singapore–Hebrew University Alliance for Research and Enterprise.
== Disease relevance == The presence of serum prolidase in the blood is a good indicator of the presence and severity of many types of diseases. For instance, Type 2 Diabetes mellitus patients have elevated levels of serum prolidase. This is expected because high blood glucose leads to a decrease in collagen production and inflammatory cell generation, which depreciates wound healing ability. Furthermore, Rheumatoid Arthritis, Ankylosing spondylitis, and benign joint hypermobility syndrome have corresponded with low serum prolidase levels. Prolidase has become a prominent marker of cancer progression in patients with various types of cancer. Depending on the elevated levels of serum prolidase in the blood, physicians are able to determine tumor size, stage of cancer, and prognosis, all of which help significantly in treating these diseases. Analysis of serum prolidase levels has been used to detect the severity of liver disease in some instances. Research has indicated the correlation between chronic liver diseases and serum prolidase. For instance, one study suggested an increase in serum prolidase levels during the initial stages of cirrhotic liver fibrosis, followed by a decrease as the disease progressed. Moreover, analysis of serum prolidase levels in alcoholic hepatitis patients has displayed higher levels compared to cirrhosis patients. Serum prolidase is a highly necessary enzyme in the human body. Through its many functions, most notably collagen recycling, prolidase is widely used in the overall metabolism of humans.
Factor VIII is bound to VWF while inactive in circulation; factor VIII degrades rapidly when not bound to VWF. Factor VIII is released from VWF by the action of thrombin. In the absence of VWF, factor VIII has a half-life of 1–2 hours; when carried by intact VWF, factor VIII has a half-life of 8–12 hours. VWF binds to collagen, e.g., when collagen is exposed beneath endothelial cells due to damage occurring to the blood vessel. Endothelium also releases VWF which forms additional links between the platelets' glycoprotein Ib/IX/V and the collagen fibrils VWF binds to platelet GpIb when it forms a complex with gpIX and gpV; this binding occurs under all circumstances, but is most efficient under high shear stress (i.e., rapid blood flow in narrow blood vessels, see below). VWF binds to other platelet receptors when they are activated, e.g., by thrombin (i.e., when coagulation has been stimulated). VWF plays a major role in blood coagulation. Therefore, VWF deficiency or dysfunction (von Willebrand disease) leads to a bleeding tendency, which is most apparent in tissues having high blood flow shear in narrow vessels. From studies it appears that VWF uncoils under these circumstances, decelerating passing platelets. Recent research also suggests that von Willebrand Factor is involved in the formation of blood vessels themselves, which would explain why some people with von Willebrand disease develop vascular malformations (predominantly in the digestive tract) that can bleed excessively.
Sources: en.wikipedia.org
No. It is a laboratory-synthesized analog built on a fragment of the natural hormone. The natural peptide is shorter-lived and lacks the stabilizing substitutions found in the synthetic version.
DAC stands for drug affinity complex, a chemical group that binds the peptide to serum albumin. The binding slows clearance and lengthens the time the molecule stays in plasma compared with the unmodified analog.
Because two distinct molecules are discussed under one informal label. The albumin-binding version clears over several days, while the form without that group clears within roughly half an hour. Mixing results from both creates inconsistent figures.
Cool, dark, and dry conditions are standard, with storage at minus twenty degrees Celsius or below. Desiccant and sealed vials limit moisture uptake. Repeated warming and cooling of the container is generally avoided.