If you have been reading about GHRH analog 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 2025-11-01. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Research material is normally supplied as a freeze-dried powder in sealed vials. In that state the peptide is comparatively robust, but prolonged exposure to warmth, moisture, or light accelerates degradation. Storage at minus twenty degrees Celsius or lower, with desiccant and protection from light, is the commonly described practice. Vials should be allowed to reach room temperature before opening to limit condensation on the powder. Moisture uptake during handling is a recognized source of variability in later measurements.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white lyophilized powder | Visual descriptor; not a measure of purity |
| Solubility class | Freely soluble in water | Aqueous dissolution may require gentle mixing |
| Typical storage (powder) | −20 °C or below, desiccated | Protect from light and ambient moisture |
| Typical storage (solution) | 2–8 °C, short term | Freeze aliquots where longer holding is needed |
| Purity assessment | Reversed-phase HPLC, area percent | Values depend on column, gradient, and detection wavelength |
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.
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.
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.
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.
There are a variety of methods and machinery that can be used to perform extraction, but the general concept is that the leaves are treated with a solvent in order to extract the compounds within them. In the aforementioned study, it was stated that the maximum yield of solids that could be extracted was 35%. Over time, other chemical methods of increasing extraction yields have been discovered, such as using hydrogen peroxide on extracted leaves to obtain a yield of 42% solids. After the extraction step, the solution is clarified by passing through a decanter, centrifuge, or filter press. Stripping is a physical separation process where components can be removed from a liquid stream through usage of a vapor stream. The stripping gas, typically steam, nitrogen, or carbon dioxide, passes through the liquid solution and dissolves the aromatic compounds within it. Aroma compounds are easily volatilized into the air. For this reason, passing gas through the liquid provides a favorable condition for the compounds to leave the liquid. The equation for determining the rate of mass transfer between a food and the gas phase is:
Hydrogen sulfide is about one-half as toxic as hydrogen cyanide, and intoxicates by the same mechanism (inhibition of the respiratory enzyme cytochrome oxidase), though hydrogen sulfide is less likely to cause sudden poisonings from small inhaled amounts (near its permissible exposure limit (PEL) of 20 ppm) because of its disagreeable odor. However, its presence in ambient air at concentration over 100–150 ppm quickly deadens the sense of smell, and a victim may breathe increasing quantities without noticing until severe symptoms cause death. Dissolved sulfide and hydrosulfide salts are toxic by the same mechanism.
The Cortlandt Street station on the New York City Subway's IRT Broadway–Seventh Avenue Line was also in close proximity to the World Trade Center complex, and the entire station, along with the surrounding track, was reduced to rubble. The station was rebuilt and reopened to the public on September 8, 2018.
Sources: en.wikipedia.org
== Further reading == Marshall JD, Beck S, Maffei P, Naggert JK (2007). "Alström syndrome". Eur. J. Hum. Genet. 15 (12): 1193–202. doi:10.1038/sj.ejhg.5201933. PMID 17940554. Alfonso Ortigado., et al. "Semaglutide in Alström Syndrome: An Improvement in the Natural Course of Cardiomyopathy". EC Paediatrics 14.7 (2025): 01-07. Berkower C. Voice of the Patient Report [Internet]. Alstrom Syndrome International; 2022 [cited 2024 Aug 22]. Available from: https://www.alstrom.org/wp-content/uploads/2023/05/ASI-EL-PFDD_FINAL_8May23.pdf Knorz VJ, Spalluto C, Lessard M, Purvis TL, Adigun FF, Collin GB, Hanley NA, Wilson DI, Hearn T (2010): Centriolar association of ALMS1 and likely centrosomal functions of the ALMS motif-containing proteins C10orf90 and KIAA1731. Mol Biol Cell (21):3617-3629. Koc E, Bayrak G, Suher M, Ensari C, Aktas D, Ensari A (2006): Rare case of Alstrom syndrome without obesity and with short stature, diagnosed in adulthood. Nephrology11(2):81-84. Roy A, Patel L, Yuan M, O'Shea C, Alvior AMB, Charalambides M, Moxon D, Baig S, Bunting KV, Gehmlich K, Geberhiwot T, Steeds RP. Defining the cardiovascular phenotype of adults with Alström syndrome. Int J Cardiol. 2024 Aug 15;409:132212. doi: 10.1016/j.ijcard.2024.132212. Epub 2024 May 26. PMID 38806112.
== Diagnosis == A combination of clinical findings and laboratory tests are used to diagnose the syndrome. Initially, individuals are screened for symptoms and have their blood sugar levels analyzed. The two principle tests used to determine insulin resistance are the fasting plasma glucose test (FPG) and the oral glucose tolerance test (GTT). Results from a patient with severe insulin resistance will show values exceeding healthy ranges (≤99 mg/dL for FPG and ≤139 mg/dL for GTT) by over 50 units. A genetic history is also established to determine risk of recurrence in the family. Based on the combination of these findings, an appropriate diagnosis is made. Rabson–Mendenhall syndrome is commonly associated with Donohue syndrome, also known as leprechaunism. Both diseases are autosomal recessive disorders caused by mutations on chromosome 19. Severe insulin resistance and an irregular enlargement of the genitalia are also overlapping symptoms.
Durham County Council itself became a unitary authority on 1 April 2009, when the seven remaining non-metropolitan districts of the county were abolished and the county council absorbed their functions. The legislation which made the county council a unitary authority allowed the council to omit the word 'County' from its name to become 'Durham Council', but in the event the name 'Durham County Council' was kept. In 2024 a combined authority was established covering Durham, Gateshead, Newcastle upon Tyne, North Tyneside, Northumberland, South Tyneside and Sunderland, called the North East Mayoral Combined Authority. It is chaired by the directly elected Mayor of the North East and oversees the delivery of certain strategic functions across the area.
The nervous system consists of the body's neurons and glial cells, which together form the nerves, ganglia and gray matter, which in turn form the brain and related structures. The brain is the organ of thought, emotion, memory, and sensory processing; it serves many aspects of communication and controls various systems and functions. The special senses consist of vision, hearing, taste, and smell. The eyes, ears, tongue, and nose gather information about the body's environment. From a structural perspective, the nervous system is typically subdivided into two component parts: the central nervous system (CNS), composed of the brain and the spinal cord; and the peripheral nervous system (PNS), composed of the nerves and ganglia outside the brain and spinal cord. The CNS is mostly responsible for organizing motion, processing sensory information, thought, memory, cognition and other such functions. It remains a matter of some debate whether the CNS directly gives rise to consciousness. The peripheral nervous system (PNS) is mostly responsible for gathering information with sensory neurons and directing body movements with motor neurons. From a functional perspective, the nervous system is again typically divided into two component parts: the somatic nervous system (SNS) and the autonomic nervous system (ANS). The SNS is involved in voluntary functions like speaking and sensory processes. The ANS is involved in involuntary processes, such as digestion and regulating blood pressure. The nervous system is subject to many different diseases.
Sources: en.wikipedia.org
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.
There is no single agreed limit, and laboratory practice varies widely. Refrigeration slows degradation, and freezing aliquots is often described for longer holding. Any visible cloudiness or precipitate indicates the solution should be discarded.
Mass spectrometry provides the most direct confirmation through molecular mass. Reversed-phase chromatography supports purity assessment, and peptide mapping or amino acid analysis can corroborate sequence. No single method establishes both purity and identity on its own.
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.