This is a working overview of RP-HPLC, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-05-10 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 |
Reported half-lives differ widely between the two variants and between species. Values for the albumin-binding form are usually expressed in days, while the unconjugated form is measured in minutes to a few hours. Sampling schedules, assay sensitivity, and route of administration all influence the numbers, which limits direct comparison across studies. Whether sustained receptor occupancy produces different downstream effects from pulsatile stimulation remains an open question in the published work. Claims about relative potency should therefore be read alongside the specific study design that produced them.
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.
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.
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.
Vitamin A is a fat-soluble vitamin that is an essential nutrient. The term "vitamin A" encompasses a group of chemically related organic compounds that includes retinol, retinyl esters, and several provitamin (precursor) carotenoids, most notably β-carotene (beta-carotene). Vitamin A has multiple functions: growth during embryo development, maintaining the immune system, and healthy vision. For aiding vision specifically, it combines with the protein opsin to form rhodopsin, the light-absorbing molecule necessary for both low-light (scotopic vision) and color vision. Vitamin A occurs as two principal forms in foods: 1) retinoids, found in animal-sourced foods, either as retinol or bound to a fatty acid to become a retinyl ester, and 2) the carotenoids α-carotene (alpha-carotene), β-carotene, γ-carotene (gamma-carotene), and the xanthophyll beta-cryptoxanthin (all of which contain β-ionone rings) that function as provitamin A in herbivore and omnivore animals which possess the enzymes that cleave and convert provitamin carotenoids to retinol. Some carnivore species lack this enzyme. The other carotenoids do not have retinoid activity. Dietary retinol is absorbed from the digestive tract via passive diffusion. Unlike retinol, β-carotene is taken up by enterocytes by the membrane transporter protein scavenger receptor B1 (SCARB1), which is upregulated in times of vitamin A deficiency (VAD). Retinol is stored in lipid droplets in the liver.
=== Public safety === The Raleigh Fire Department provides fire protection throughout the city. The North Carolina Correctional Institution for Women, the state's primary correctional facility housing female inmates, is based in Raleigh.
== Selected publications == Ammann AJ and Stiehm ER. Immune Globulin Levels in Colostrum and Breast Milk, and Serum From Formula- and Breast-Fed Newborns.[link removed] Proc Soc Exp Biol Med, 122:1098-1100, 1966. Stiehm ER, Ammann AJ, Cherry JD. Elevated cord macroglobulins in the diagnosis of intrauterine infections. NEJM, 275:971-977, 1966. Ammann AJ, Wara D, Salmon S, Perkins H. Thymus transplantation. Thymus Transplantation — Permanent Reconstitution of Cellular Immunity in a Patient with Sex-Linked Combined Immunodeficiency. NEJM, 289:5-9, 1973. Wara DW, Goldstein AL, Doyle NE, Ammann AJ. Thymosin Activity in Patients with Cellular Immunodeficiency. NEJM, 292:70-74, 1975. (One of the 500 most widely quoted articles in 1980, Citation Classic) Giblett ER, Ammann AJ, Sandman R, Wara DW, Diamond LK. Nucleoside-phosphorylase deficiency in a child with severely defective T-cell immunity and normal B-cell immunity. Lancet, 1:2020-1014, 1975. (One of the 500 most widely quoted articles in 1984, Citation Classic) Ammann AJ, Addiego J, Wara DW, Lubin B, Smith WB, Mentzer WC. Polyvalent pneumococcal-polysaccharide immunization of patients with sickle-cell anemia and patients with splenectomy. NEJM, 297:897-900, 1977. Ammann AJ, Cowan MJ, Wara DW, Weintrub P, Dritz S, Goldman H, Perkins HA. Acquired immunodeficiency in an infant: Possible transmission by means of blood products. Lancet, 1:956-958, 1983.
== Pharmacokinetics == Synthetic cannabinoids are delivered by smoking. In a human study, after 50 μg/kg smoked JWH-018 are delivered, one male and a female have their serum concentration of 8.1 and 10.2 μg/L respectively after 5 minutes, down to 4.6 and 6.1 μg/L after 15 minutes, suggesting the biological half-life of JWH-018 is short. 13 phase 1 metabolites are identified. Monohydroxylated and dihydrodiol metabolites are most prevalent metabolites of synthetic cannabinoids. UGT1A1, UGT1A3, UGT1A9, UGT1A10 and UGT2B7 isoenzymes were primarily responsible for JWH-018 and JWH-073 metabolites' conjugation and had high affinity for hydroxylated metabolites (Km=12–18 mmol/L). Generation of JWH-018-N-4- and 5-hydroxypentyl (JWH-018 metabolites) was primarily mediated by CYP2C9 followed by CYP1A2 and CYP2C19. CYP3A4 catalyzed JWH-018-N-4-hydroxypentyl production but with lower activity than CYP1A2 and CP2C19. The drugs are mainly excreted as urine. Phenethylamines are first-order kinetics with half life of 5 to 10 minutes which are absorbed by ingestion. The drugs have low concentration in the brain due to low biological half-life. It is difficult to measure the plasma concentration due to low stability of Phenethylamine. There are two possible metabolism pathways. The first possible pathway is metabolism by MAO-B (an intracellular enzyme mainly in the brain and tightly bound to the outer membrane of mitochondria which deaminates free primary and secondary amines) to form phenylacetic acid due to MAO-B selectivity on non-polar aromatic amines.
Sources: en.wikipedia.org
Bats are the only mammals that can truly fly. They fly through the air at a constant speed by moving their wings up and down (usually with some fore-aft movement as well). Because the animal is in motion, there is some airflow relative to its body which, combined with the velocity of the wings, generates a faster airflow moving over the wing. This generates a lift force vector pointing forwards and upwards, and a drag force vector pointing rearwards and upwards. The upwards components of these counteract gravity, keeping the body in the air, while the forward component provides thrust to counteract both the drag from the wing and from the body as a whole. The wings of bats are much thinner and consist of more bones than those of birds, allowing bats to maneuvere more accurately and fly with more lift and less drag. By folding the wings inwards towards their body on the upstroke, they use 35% less energy during flight than birds. The membranes are delicate, ripping easily; however, the tissue of the bat's membrane is able to regrow, such that small tears can heal quickly. The surface of their wings is equipped with touch-sensitive receptors on small bumps called Merkel cells, also found on human fingertips. These sensitive areas are different in bats, as each bump has a tiny hair in the center, making it even more sensitive and allowing the bat to detect and collect information about the air flowing over its wings, and to fly more efficiently by changing the shape of its wings in response.
=== Film and other TV appearances === In addition to the game shows for which he became famous, Barker also hosted the annual/biennial Pillsbury Bake-Off (the bake-off occurred every two years starting in 1976). In 1978, he was the first host to have a male category champ. From 1969-1988 he also co-hosted CBS's coverage of the Rose Parade from Pasadena, California. On September 7, 2009, Barker was a special guest host for WWE Raw (called "The Price is Raw") in Rosemont, Illinois. Aired during a period when nearly every episode of the weekly wrestling show featured a celebrity guest host, with mixed results, Barker's appearance has been ranked the best of nearly 80 hosts. Barker also agreed to be a rotating guest co-host on The Huckabee Show, a daily TV talk show hosted by Mike Huckabee. Barker first appeared on the show on July 29, 2010. Barker's fame from his television hosting roles also saw him become a popular guest on other shows, including as a semi-regular panelist on the game shows Tattletales (1975–1976, with wife Dorothy Jo) and Match Game (1973–1980). Barker sat in Richard Dawson's former place during the first week after Dawson permanently left Match Game. Barker also made appearances on various talk shows such as: Dinah!, Larry King Live, The Arsenio Hall Show, Crook & Chase, Donny & Marie, The Rosie O'Donnell Show, The Ellen DeGeneres Show, The Wayne Brady Show, the Late Show with David Letterman, and The Late Late Show with Craig Ferguson.
Loop type, in which the primary coolant is circulated through primary heat exchangers outside the reactor tank (but inside the biological shield due to radioactive 24Na in the primary coolant) Pool type, in which the primary heat exchangers and pumps are immersed in the reactor tank There are only two commercially operating breeder reactors as of 2017: the BN-600 reactor, at 560 MWe, and the BN-800 reactor, at 880 MWe. Both are Russian sodium-cooled reactors. The designs use liquid metal as the primary coolant, to transfer heat from the core to steam used to power the electricity generating turbines. FBRs cooled by liquid metals other than sodium have been built, some early FBRs such as Clementine used mercury, Lead-cooled fast reactor have also been constructed, as well as other experimental reactors using Lead-bismuth eutectic or NaK, a sodium-potassium alloy. Mercury and NaK have the advantage that they are liquids at room temperature, which is convenient for experimental rigs but less important for pilot or full-scale power stations, where their chemical toxicity and cost respectively leave them as less attractive options. The Soviet Union used lead–bismuth coolant in some naval reactors. BREST-OD-300 is a later Russian design that uses lead coolant. Its first concrete was poured in June 2021. The SVBR-100 design specifies lead-bismuth eutectic as its coolant. Three of the proposed generation IV reactor types use a fast-neutron spectrum:
==== Attenuated ==== The idea of wildlife vaccination was conceived during the 1960s, and modified-live rabies viruses were used for the experimental oral vaccination of carnivores by the 1970s. Development of an oral immunization for wildlife began in the United States with laboratory trials using the live, attenuated Evelyn-Rokitnicki-Abelseth (ERA) vaccine, derived from the Street Alabama Dufferin (SAD) strain. The first ORV field trial using the live attenuated vaccine to immunize foxes occurred in Switzerland during 1978. Modified live virus vaccines may use strains such as SAG2 and SAD B19..
=== Dispensing assistants === Dispensing assistants are commonly referred to as "dispensers" and in community pharmacies perform largely the same tasks as a pharmacy technician. They work under the supervision of pharmacists and are involved in preparing (dispensing and labelling) medicines for provision to patients.
Sources: en.wikipedia.org
== Target and function == Heparan sulfate analogues are thought to display identical properties as heparan sulfate with exception of being stable in a proteolytic and glycolytic environment like a wound. Because heparan sulfate is broken down in chronic wounds by heparanase, the analogues only bind at sites where natural heparan sulfate is absent. Also the function of the heparan sulfate analogues is the same as heparan sulfate: structuring the ECM scaffold and protecting a variety of protein ligands such as ECM proteins growth factors and cytokines. By positioning and keeping them in place, in a reconstituted organization mimicking that of before the wound, the tissue can then use these different proteins properly and spatially displayed for inducing cell migration, proliferation and differentiation. This results in improved tissue repair and sometimes a real regeneration process.
The stand-off cost three demonstrators their lives in clashes with the army on the night of 20–21 August before the coup leaders, lacking the broad military backing they needed and rapidly losing the fear that had sustained their authority, lost their nerve; Estonia and Latvia seized the moment to declare independence, and coup leader Boris Pugo took his own life rather than face arrest. Gorbachev formally resumed his powers on returning to Moscow, but by then the substance of power had already passed elsewhere—the Communist Party did not even condemn its own plotters until 21 August, by which point Yeltsin had exploited its paralysis to ban the Party outright within the Russian federation. Yeltsin's courage in personally defending the parliament building may have helped break the putsch but at the cost of Gorbachev's remaining authority.
Branco ("White") is a rare variety local to the Amazon estuary in which the berries do not change color, but remain green when ripe. This is believed to be due to a recessive gene since only about 30% of 'Branco' palm seeds mature to express this trait. BRS-Pará was developed in 2004 by the Brazilian Agricultural Research Agency. The pulp yield ranges from 15% to 25%. BRS Pai d'Égua is the newest cultivar developed by the Brazilian Agricultural Research Agency.
== Function == Protein kinase C (PKC) is a family of serine- and threonine-specific protein kinases that can be activated by calcium and the second messenger diacylglycerol. PKC family members phosphorylate a wide variety of protein targets and are known to be involved in diverse cellular signaling pathways. PKC family members also serve as major receptors for phorbol esters, a class of tumor promoters. Each member of the PKC family has a specific expression profile and is believed to play a distinct role in cells. The protein encoded by this gene is one of the PKC family members. This kinase has been shown to be involved in many different cellular functions, such as apoptosis, cardioprotection from ischemia, heat shock response, as well as insulin exocytosis.
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.