If you have been reading about modified GRF(1-29) 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 2025-08-22. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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 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.
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.
| 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 |
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.
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.
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.
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.
Pharmacokinetic behaviour differs sharply between the two forms. The DAC-bearing peptide shows an extended circulation time measured in days, whereas the version without the complex is cleared within roughly half an hour. This gap shapes how researchers design dosing schedules in animal models. Whether the prolonged presence of the DAC form produces effects meaningfully different from the short-acting variant remains an open question, since comparative human data are scarce.
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.
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== Biosynthesis == 1-Methylnicotinamide can be produced in the liver by nicotinamide N-methyltransferase (NNMT). The reaction takes place during the metabolism of NAD+ (nicotinamide adenine dinucleotide). NNMT is also present in brain tissue, adipose tissue, muscle tissue, kidneys, and skin. NNMT (nicotinamide N-methyltransferase) is an enzyme that in humans is encoded by the NNMT gene. NNMT catalyzes the methylation of nicotinamide and similar compounds using the methyl donor S-adenosyl methionine (SAM-e) to produce S-adenosyl-L-homocysteine (SAH) and 1-methylnicotinamide. NNMT is highly expressed in the human liver.
The Streptavidin-Binding Peptide (SBP)-Tag is a 38-amino acid sequence that may be engineered into recombinant proteins. Recombinant proteins containing the SBP-Tag bind to streptavidin and this property may be utilized in specific purification, detection or immobilization strategies. The sequence of the SBP tag is MDEKTTGWRGGHVVEGLAGELEQLRARLEHHPQGQREP.
Sources: en.wikipedia.org
== As vaccine or adjuvant == Peptidoglycan is immunologically active, which can stimulate immune cells to increase the expression of cytokines and enhance antibody-dependent specific response when combined with vaccine or as adjuvant alone. MDP, which is the basic unit of peptidoglycan, was initially used as the active component of Freund's adjuvant. Peptidoglycan from Staphylococcus aureus was used as a vaccine to protect mice, showing that after vaccine injection for 40 weeks, the mice survived from S. aureus challenge at an increased lethal dose.
=== Other uses === Beta blockers like propranolol may be useful in the treatment of aggression and agitation in contexts like people with schizophrenia or psychosis, brain injuries, and intellectual disabilities. Beta blockers are frequently used to treat akathisia and may be considered a first-line therapy for this indication. Akathisia is a type of extrapyramidal symptom often associated with antipsychotics used to treat psychotic disorders like schizophrenia. Propranolol is the most-studied beta blocker for treatment of akathisia, whereas very limited data suggest that metoprolol may provide comparable benefits, and nadolol, which is peripherally selective, does not appear to be effective. Adrenergic antagonists are mostly used for cardiovascular disease. The adrenergic antagonists are widely used for lowering blood pressure and relieving hypertension. These antagonists have been proven to relieve the pain caused by myocardial infarction, and also the infarction size, which correlates with heart rate. Beta blockers are used to treat acute cardiovascular toxicity (e.g. in overdose) caused by sympathomimetics, for instance caused by amphetamine, methamphetamine, cocaine, ephedrine, and other drugs. Combined α1 and beta blockers like labetalol and carvedilol may be more favorable for such purposes due to the possibility of "unopposed α-stimulation" with selective beta blockers like propranolol and atenolol.
== Symptoms == D. dadantii is phytopathogenic bacterium causing soft rot diseases on many host plants including some which are economically important. D. dadantii, more commonly known as: soft rot, brown rot or blackleg, causes characteristic symptoms associated with other bacterial wilts, causing final diagnosis to be difficult. The pathogen primarily seeks to attack the plant's xylem vessels located in leaves, stems, blossoms and storage organs of herbaceous plants. D. dadantii is able to infect hosts at any point in its life cycle. In addition to symptoms of wilt, the disease appears as sunken and cracked external lesions also having a brown interior in cross section in subterranean bulbs and tubers Diseased plants will display a variety of symptoms including: wilting, stunting and vascular discoloration of the stems. Early symptoms include water soaked lesions at the site of infection, gradually expanding chlorotic leaves and loss of turgor in tissues. The intensity of D. dadantii colonization relates to the amount of disease and degree of damage. The pathogen is very successful at infiltrating host tissues due to the many pectinases responsible for disassembly of plant cell wall polysaccharides. Once the cell wall is degraded cellular structure collapses and this cell maceration gives a characteristic "water-soaked" or rotted appearance. D. dadantii grow intercellularly, continuing to degrade cells and colonize, until it eventually reaches xylem tissues. Upon reaching the xylem vessels D.
Chemical modification of wood. Wood and Fiber Sci., 26(2):270-280. Langrish, T.A.G. and Walker, J.C.F. (1993). Transport Processes in Wood. In: Walker, J.C.F. Primary Wood Processing. Chapman and Hall, London. pp121–152. Panshin, A.J. and de Zeeuw, C. (1970). Textbook of Wood Technology. Volume 1, Third Edition. McGraw-Hill, New York, 705 p. Pordage, L.J. and Langrish, T.A.G. (1999). Simulation of the effect of air velocity in the drying of hardwood timber. Drying Technology - An International Journal, 17(1&2):237-256. Rasmussen, E.F. (1988). Forest Products Laboratory, U.S. Department of Agriculture. (ed.). Dry Kiln Operators Manual. Hardwood Research Council. Rowell, R.M. (1983). Chemical modification of wood. Forest Product Abstract, 6(12):363-382. Rowell, R.M. (1991). Chemical Modification of Wood. In: Hon, D.N.-S and Shiraishi, N. (eds), Wood and Cellulosic Chemistry. pp. 703–756. Marcel Dekker, Inc., New York. Siau, J.F. (1984). Transport processes in wood. Springer-Verlag, New York. 245p. Sjostrom, E. (1993). Wood Chemistry: Fundamentals and Applications. Academic Press Limited, London. 293p. Skaar, C. (1988). Wood Water Relations. Springer-Verlag, New York. 283p. Stamm, A. J. (1964). Wood and Cellulose Science. Ronald Press, New York. 509p. Standard Australia (2000). Timber - Classification into Strength Groups. Australian/New Zealand Standard (AS/NZS) 2878. Sydney. 36p. Standard Australia (2001). Timber - Assessment of Drying Quality. Australian/New Zealand Standard (AS/NZS) 4787. Sydney. 24p. Strumillo, C. and Kudra, T. (1986).
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.
The powder is normally held at minus twenty degrees Celsius or below. Light and moisture exposure should be minimized. Repeated warming and cooling cycles are avoided.