Lyophilized powder 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 2025-11-23 and is reviewed periodically as new material appears.
CJC-1295 is a synthetic peptide designed as a long-acting analogue of growth hormone-releasing hormone (GHRH). Its structure derives from the first 29 amino acids of native GHRH, a fragment often called GRF(1-29). Four substitutions were introduced to slow enzymatic breakdown and extend activity relative to the natural sequence. The compound was developed by ConjuChem as part of a broader effort to improve the pharmacokinetic profile of peptide hormones. It is studied in laboratory and clinical research settings rather than appearing as a naturally occurring substance.
Two related forms circulate in technical discussion under the same family name. The original version carries a drug affinity complex (DAC) that binds covalently to serum albumin after administration, and this linkage substantially extends circulation time. A second form, frequently written as modified GRF(1-29) or CJC-1295 without DAC, lacks that linker and clears much faster. The naming is a frequent source of confusion because the shorthand CJC-1295 can refer to either form depending on the source. Reports sometimes fail to specify which variant was studied.
The peptide backbone includes a D-alanine at position two, which resists cleavage by dipeptidyl peptidase IV, and several other substitutions that reduce degradation. Its molecular weight is roughly 3.4 kDa without the linker and about 3.6 kDa with it. The molecule is water soluble and is normally supplied as a lyophilized powder. Precise sequence and mass values depend on which variant is described, so technical documents usually state the exact form being referenced.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular weight (no linker) | ~3.37 kDa | Calculated from peptide sequence |
| Molecular weight (with linker) | ~3.65 kDa | Includes albumin-binding moiety |
| Appearance | White to off-white powder | Typically lyophilized |
| Solubility | Soluble in water | Also dissolves in aqueous buffers |
| Common synonyms | Modified GRF(1-29), DAC:GRF | Usage varies by source |
Lyophilised powder is the usual supplied form. The material is hygroscopic, so vials are typically equilibrated to room temperature before opening in order to prevent condensation on the contents. Long-term storage is generally described at minus twenty degrees Celsius or colder, protected from light and moisture. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of soluble material. A reconstituted solution is considerably less stable than the dry powder and is normally kept refrigerated for short periods only.
Identity and purity are assessed mainly by reversed-phase high-performance liquid chromatography combined with mass spectrometry. The chromatographic separation resolves the target peptide from truncation products and from species carrying oxidised residues, while mass measurement confirms the expected molecular mass. Because the two common variants differ by roughly 280 daltons, a mass determination distinguishes them unambiguously. Purity is often quoted as a percentage of total peak area, although that figure depends on the detection wavelength and the integration method applied.
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.
CJC-1295 is a synthetic analogue of growth hormone-releasing hormone, built on the 29-amino-acid GHRH(1-29) fragment. Four substitutions distinguish it from the natural sequence: D-alanine at position 2, glutamine at position 8, alanine at position 15, and leucine at position 27. These changes reduce enzymatic cleavage and extend the peptide's persistence in circulation. The compound is discussed in two forms, one carrying a drug affinity complex and one without it.
The drug affinity complex is a maleimidopropionic acid group attached to a lysine side chain. It reacts with the free thiol of cysteine-34 on circulating albumin, forming a covalent bond. This conjugation keeps the peptide in the bloodstream and shields it from rapid renal filtration and proteolysis. Reported circulation half-lives for the albumin-bound form fall in the range of roughly six to nine days in early human studies.
=== Schizophrenia === Schizophrenia is a chronic mental health condition caused by changes in brain chemistry and structure. Genetics and environment are hypothesized to play a key role in development of this disorder. Research suggests impaired gene expression or chemical imbalance may impact this condition. Anxiety can increase risk of schizophrenia and symptoms include hallucinations, disorganized speech, and abnormal behavior. Davunetide (NAP) is a segment of activity-dependent neuroprotective protein (ADNP). ADNP is reported be downregulated with schizophrenia. A study observed decreased hyperactivity in mice when treated with NAP via the intranasal route.
== Grants == In 1985, the Society used the proceeds from the 10th International Mass Spectrometry Conference to establish 7 Beynon PhD Studentships. In 2007, the Society announced they would initiate summer studentship projects and in 2012 they announced BMSS research grants.
=== Pregnancy and breastfeeding === Research on animal reproduction has indicated that there is a trace of teratogenicity when doses are reduced by 10 times the human recommended dose. There is no sufficient information on human pregnancy at this moment. Use is only recommended when the potential benefits outweigh the potential risks for the pregnant mother and the fetus. Prednisolone when delivered systemically can be found in the mother's breast milk, however, there is no data provided for the extent of prednisolone found in the system after administering eye drops. However, the presence of corticosteroids is recorded when they are administered systemically, and it could affect the fetus' growth. Therefore, the use of prednisolone during breastfeeding is not advocated.
Sources: en.wikipedia.org
Vacuum, used in small lamps. Provides best thermal insulation of the filament but does not protect against its evaporation. Used also in larger lamps where the outer bulb surface temperature has to be limited. Argon (93%) and nitrogen (7%), where argon is used for its inertness, low thermal conductivity and low cost, and the nitrogen is added to increase the breakdown voltage and prevent arcing between parts of the filament. Nitrogen, used in some higher-power lamps, e.g. projection lamps, and where higher breakdown voltage is needed due to proximity of filament parts or lead-in wires. Krypton, which is more advantageous than argon due to its higher atomic weight and lower thermal conductivity (which also allows use of smaller bulbs), but its use is hindered by much higher cost, confining it mostly to smaller-size bulbs. Krypton mixed with xenon, where xenon improves the gas properties further due to its higher atomic weight. Its use is however limited by its very high cost. The improvements by using xenon are modest in comparison to its cost. Hydrogen, in special flashing lamps where rapid filament cooling is required; its high thermal conductivity is exploited here. Halogen, a small amount mixed with inert gas which is used in halogen lamps, a distinct type of incandescent lamp. The gas fill must be free of traces of water, which greatly accelerates bulb blackening (see below). The gas layer close to the filament (called the Langmuir layer) is stagnant, with heat transfer occurring only by conduction.
Protein efficiency ratio (PER) is the ratio of weight gain to the amount of protein ingested. It is usually tested with rats. Biological value (BV) essentially estimates the proportion of food nitrogen kept in the body by subtracting out nitrogen found in urine and feces. Nitrogen is assumed to originate from protein. Net protein utilization (NPU) is similar, except it only subtracts out urine nitrogen. They are methods based on nitrogen balance. Modern measurements analyze two separate aspects: protein digestibility and amino acid balance. The former is measured by comparing how much protein is found in the food before and after it goes through the digestive tract or a part of it. The latter is measured by taking the amino acid profile of a protein and comparing it to essential amino acid needs of an organism, typically humans.
Later, during the 1990s, Heseltine committed a minor gaffe when he joked in a speech about how he had strung creditors along. Between 1960 and 1964, Heseltine also worked as a part-time interviewer for ITV, very likely, in Crick's view, to maintain his public profile as an aspiring politician.
Sources: en.wikipedia.org
17 September Jaws in the Med about swimming in the Mediterranean Sea; on Friday 20 July 1956 Royal Navy English teacher at Valletta Naval Technical School, forty-year-old Jack Smedley, went for a swim in St Thomas' Bay in Malta, when he was attacked by a great white shark, and never seen again; on 17 April 1987 a similar shark was landed by a fishing boat at Żurrieq in Malta, later researched by BBC weather presenter Ian Fergusson; board sailor José Luis Pérez-Díaz was attacked by a shark on 18 March 1986 at Tarifa in Andalusia, losing his foot; on Thursday 2 February 1989 scuba diver 47-year-old Luciano Constanzo was attacked by a 6-metre shark at Baratti in Tuscany, being the first shark attack in Italy for 27 years; sharks had been seen around Favignana, and its Mattanza; Franco Cigala-Fulgosi of the University of Parva; Giuseppe Notarbartolo di Sciara of the Tethys Research Institute, and how pollution from the Po (river) has damaged life in the Adriatic Sea. Narrated by Bob Peck, produced by Frances Berrigan, directed by Jeremy Taylor, made by Cicada Films with Discovery Communications 24 September Under Fire, about current firefighting technology; it was made coincide with National Fire Safety Week; the dangers such as flashover, when combustible gases ignite at the same time, sometimes explosively; it featured York fire station officer John Taylor, and Harrogate fireman Stephen Fairweather, who looked at fires in this country and Sweden; Sweden began training for flashovers in 1984, and no-one has been killed since through that.
== Applications == The remarkable stability of cyclotides means that they have an exciting range of potential applications centred on either their intrinsic biological activities or the possibility of using the CCK motif as a scaffold for stabilizing biologically active epitopes. Interest in these has recently intensified with the publications of a chemical methodology capable of synthetically producing cyclotides with high yields, and the amenability of the CCK framework to amino-acid substitutions. But for molecules to be useful in a therapeutic setting they require useful biopharmaceutical characteristics such as resistance to proteolysis and membrane permeability. The membrane interactive surface area and moment of the cyclotides are determinants in the prediction of their biological activities. A recent study on related cystine knot proteins as drug candidates showed that cystine knots do permeate well through rat small intestinal mucosa relative to non-cystine knot peptide drugs such as insulin and bacitracin. Furthermore, enzymatic digestion of cystine knot peptide drugs was associated with only a few proteases and it was suggested that this limitation may be overcome by mutating out particular cleavage sites. Thus, certain cystine knot proteins satisfy the basic criteria for drug delivery and represent exciting novel candidates as scaffolds for peptide drug delivery.
== Alternative Medical Causes of Altered Turgor == Altered skin turgor can be caused by chronic medical conditions completely unrelated to an individual's immediate hydration status. Systemic sclerosis, or scleroderma, is an autoimmune disorder that triggers excessive collage production, resulting in abnormally tight, hard, and shiny skin that exhibits high turgor and cannot be pinched at all. On the other hand, genetic connective tissue disorders can drastically lower baseline skin tension, making the skin hyper-elastic. Additionally, localized fluid retention or severe edema stretches the dermis tightly, masking underlying systemic dehydration by artificially inflating skin turgor measurements.
Sources: en.wikipedia.org
No. It is a synthetic analogue modeled on the first 29 residues of human GHRH. The substitutions and any linker are laboratory modifications rather than features of the endogenous peptide.
Early development used the albumin-binding form, and a shorter variant was later discussed under the same label. Because the two differ in half-life and handling, ambiguity arises whenever a source omits the variant designation.
The compound derives from that fragment but is not identical to it. The parent fragment lacks the stabilizing substitutions, so its degradation rate and duration of action differ noticeably.
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.