albumin binding 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 2026-05-02 and is reviewed periodically as new material appears.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C152H252N44O42 | Cited for the form without the drug affinity complex |
| Molecular weight | About 3368 Da | Reported value for modified GRF(1-29) |
| Appearance | White to off-white powder | Lyophilised solid as usually supplied |
| Solubility | Soluble in water and polar solvents | Clarity depends on purity and salt content |
| Typical storage | -20 C or below, dry | Protect from light and repeated warming cycles |
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.
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.
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.
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.
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.
=== Molecular representations for chirality === Computational methods for representing molecular chirality must encode three-dimensional stereochemical information in a format suitable for machine learning algorithms. SMILES (Simplified Molecular Input Line Entry System) notation incorporates stereochemistry through the use of @ and @@ symbols at chiral centers, where @ typically denotes anticlockwise and @@ denotes clockwise configuration when viewing the chiral center along the bond from the center to the first atom in the SMILES string. Traditional molecular descriptors used in computational chemistry, such as circular fingerprints (Extended Connectivity Fingerprints or ECFP), can encode structural information including stereochemical features. These descriptors represent molecules as fixed-length binary vectors that capture local atomic environments and connectivity patterns. However, conventional fingerprints may not optimally capture the subtle three-dimensional differences between enantiomers. Neural network-based molecular representations can be derived from SMILES strings. Variational autoencoders and heteroencoders trained on large databases of molecular structures can generate latent space vectors (LSVs) that encode molecular properties in a continuous, lower-dimensional space. These methods calculate difference vectors between the descriptor of a molecule and that of its enantiomer, or between the original descriptor and one derived from a stereochemistry-depleted SMILES string.
The oxides B2O3, SiO2, GeO2, As2O3, and Sb2O3 readily form glasses. TeO2 forms a glass but this requires a "heroic quench rate" or the addition of an impurity; otherwise the crystalline form results. These compounds are used in chemical, domestic, and industrial glassware and optics. Boron trioxide is used as a glass fibre additive, and is also a component of borosilicate glass, widely used for laboratory glassware and domestic ovenware for its low thermal expansion. Most ordinary glassware is made from silicon dioxide. Germanium dioxide is used as a glass fibre additive, as well as in infrared optical systems. Arsenic trioxide is used in the glass industry as a decolourizing and fining agent (for the removal of bubbles), as is antimony trioxide. Tellurium dioxide finds application in laser and nonlinear optics. Amorphous metallic glasses are generally most easily prepared if one of the components is a metalloid or "near metalloid" such as boron, carbon, silicon, phosphorus or germanium. Aside from thin films deposited at very low temperatures, the first known metallic glass was an alloy of composition Au75Si25 reported in 1960. A metallic glass having a strength and toughness not previously seen, of composition Pd82.5P6Si9.5Ge2, was reported in 2011. Phosphorus, selenium, and lead, which are less often recognised as metalloids, are also used in glasses. Phosphate glass has a substrate of phosphorus pentoxide (P2O5), rather than the silica (SiO2) of conventional silicate glasses. It is used, for example, to make sodium lamps.
This form of asexual reproduction, called parthenogenesis, occurs in several species of gecko, and is particularly widespread in the teiids (especially Aspidocelis) and lacertids (Lacerta). In captivity, Komodo dragons (Varanidae) have reproduced by parthenogenesis. Parthenogenetic species are suspected to occur among chameleons, agamids, xantusiids, and typhlopids. Some reptiles exhibit temperature-dependent sex determination (TDSD), in which the incubation temperature determines whether a particular egg hatches as male or female. TDSD is most common in turtles and crocodiles, but also occurs in lizards and tuatara. To date, there has been no confirmation of whether TDSD occurs in snakes.
A ranking system used to describe the strength of the results measured in a clinical trial or research study. The design of the study (such as a case report for an individual patient or a randomized double-blinded controlled clinical trial) and the endpoints measured (such as survival or quality of life) affect the strength of the evidence. (NCI)
=== Jcom radio libel case === In November 2007, Jewish radio station Jcom aired a satirical segment in which a character named 'Georgie Galloway' used the anti-Semitic catchphrase "kill the Jews, kill the Jews". Galloway sued the station for libel and won the case in the High Court. Galloway was awarded £15,000 in damages and around £5,000 in costs. The radio station closed after losing the case. Galloway said the judgment had "categorically crushed the slur of anti-Semitism" against him.
Sources: en.wikipedia.org
A scandal involving 240 tons of gutter oil in Taiwan affecting hundreds of companies and thousands of restaurants, some of which may have been exported overseas, broke in September 2014. In 2018, researchers worked on identifying different components in gutter oil using 1H NMR (proton nuclear magnetic resonance), MALDI-MS (matrix-assisted laser desorption/ionization-mass spectrometry) and HPLC (high-performance liquid chromatography).
amino acid Any of a class of organic compounds whose basic structural formula includes a central carbon atom bonded to amine and carboxyl functional groups and to a variable side chain. Out of nearly 500 known amino acids, a set of 20 are coded for by the standard genetic code and incorporated into long polymeric chains as the building blocks of peptides and hence of polypeptides and proteins. The specific sequences of amino acids in the polypeptide chains that form a protein are ultimately responsible for determining the protein's structure and function.
Serine hydroxymethyltransferase (SHMT) also catalyzes the biosynthesis of glycine (retro-aldol cleavage) from serine, transferring the resulting formaldehyde synthon to 5,6,7,8-tetrahydrofolate. However, that reaction is reversible, and will convert excess glycine to serine. SHMT is a pyridoxal phosphate (PLP) dependent enzyme.
==== NATO ==== The foreign secretary, Geoffrey Howe, spoke highly of Heseltine's contribution to NATO and WEU conferences. Heseltine was as angry as Thatcher at the US invasion of Grenada, a Commonwealth country. He wanted warmer relations with the Soviets and was sceptical about the US Strategic Defense Initiative ("Star Wars"), putting in a brief and grudging appearance at Caspar Weinberger's Ditchley Park Conference about the topic in 1985. Heseltine came close to misleading the House of Commons over the meeting of NATO defence ministers at Montebello, Quebec, in October 1983. He stated that no "specific" proposals had been made to update NATO short range and tactical nuclear weapons. In fact a decision had been made in principle to do so. Crick describes Heseltine's answers as "highly disingenuous and deceitful". At the time NATO was claiming to be cutting back on such weapons, and the peace movement was still powerful in Germany where such weapons might be used.
Distribution of the Asian citrus psyllid is primarily in tropical and subtropical Asia. It has been reported in all citrus-growing regions in Asia except mainland Japan. The disease has affected crops in China, India, Sri Lanka, Malaysia, Indonesia, Myanmar, the Philippines, Pakistan, Thailand, the Ryukyu Islands, Nepal, Saudi Arabia, and Afghanistan. Areas outside Asia have also reported the disease: Réunion, Mauritius, Brazil, Paraguay, Florida since 2005, and in several municipalities in Mexico since 2009. On 30 March 2012, citrus greening disease was confirmed in a single citrus tree in California. The first report of HLB in Texas occurred on 13 January 2012, from a Valencia sweet orange tree in a commercial orchard in Texas. Prospects are bleak for the ubiquitous backyard citrus orchards of California as residential growers are unlikely to consistently use the pesticides which provide effective control in commercial orchards. The distribution of the African citrus psyllid includes Africa, Madeira, Saudi Arabia, Portugal, and Yemen. This species is sensitive to high temperatures and will not develop at temperatures greater than 25 °C (77 °F). It is a vector of the African strain of huanglongbing (Candidatus Liberibacter africanus), which is sensitive to heat. This strain is reported to occur in Africa, (Burundi, Cameroon, Central African Republic, Comoros, Ethiopia, Kenya, Madagascar, Malawi, Mauritius, Reunion, Rwanda, South Africa, St. Helena [unconfirmed], Swaziland, Tanzania, Zimbabwe), Saudi Arabia, and Yemen. The disease was not reported in the EU as of 2004.
Sources: en.wikipedia.org
== Education and career == Hong grew up in China and completed her B.A. degree in chemistry from Mount Holyoke College (summa cum laude) in 1992 and a Ph.D. degree from the University of California, Berkeley in 1996. There she worked in the laboratory of Alexander Pines to investigate phospholipid structure and dynamics using variable-angle-spinning NMR. After a one-year postdoctoral stint in the laboratory of Robert G. Griffin at the Massachusetts Institute of Technology, she went to University of Massachusetts Amherst and developed biosynthetic isotopic labeling approaches to advance protein structure determination by ssNMR. She started an assistant professorship at Iowa State University in 1999, became an associate professor in 2002 and full professor in 2004, and held the first John D. Corbett Professorship from 2007 to 2010. In 2014, she returned to the Massachusetts Institute of Technology as a professor of chemistry.
== Death == Florey published his last scientific paper, co-written with Jennings, in 1967. He had written or co-written over two hundred papers. He died at his home at the provost's lodgings, of congestive heart failure on 21 February 1968. Although Florey was an agnostic, a funeral service was held in the St. Nicholas' parish church in Marston. A memorial plaque was placed on the outside wall near the entrance; the church refused to allow it to be placed inside because Florey had been so outspoken in his disbelief. A larger service at Westminster Abbey in London was attended by about 500 people. His remains were cremated.
== Modern dating methods == Radiometric dating has been carried out since 1905 when it was invented by Ernest Rutherford as a method by which one might determine the age of the Earth. In the century since then the techniques have been greatly improved and expanded. Dating can now be performed on samples as small as a nanogram using a mass spectrometer. The mass spectrometer was invented in the 1940s and began to be used in radiometric dating in the 1950s. It operates by generating a beam of ionized atoms from the sample under test. The ions then travel through a magnetic field, which diverts them into different sampling sensors, known as "Faraday cups," depending on their mass and level of ionization. On impact in the cups, the ions set up a very weak current that can be measured to determine the rate of impacts and the relative concentrations of different atoms in the beams.
Flushing (serotonin itself does not cause flushing). Potential causes of flushing in carcinoid syndrome include bradykinins, prostaglandins, tachykinins, substance P, and/or histamine, diarrhea, and heart problems. Because of serotonin's growth-promoting effect on cardiac myocytes, a serotonin-secreting carcinoid tumour may cause a tricuspid valve disease syndrome, due to the proliferation of myocytes onto the valve. Diarrhea Wheezing Abdominal cramping Peripheral edema The outflow of serotonin can cause a depletion of tryptophan leading to niacin deficiency. Niacin deficiency, also known as pellagra, is associated with dermatitis, dementia, and diarrhea. This constellation of symptoms is called carcinoid syndrome or (if acute) carcinoid crisis. Occasionally, haemorrhage or the effects of tumor bulk are the presenting symptoms. The most common originating site of carcinoid is the small bowel, particularly the ileum; carcinoid tumors are the most common malignancy of the appendix. Carcinoid tumors may rarely arise from the ovary or thymus. They are most commonly found in the midgut at the level of the ileum or in the appendix. The next most commonly affected area is the respiratory tract, with 28% of all cases—per PAN-SEER data (1973–1999). The rectum is also a common site.
Ubayd Allah's father prepared him to succeed him as governor, and indeed, after Ziyad's death in 672/673, Ubayd Allah became governor of Khurasan. A year or two later, he was also appointed to the governorship of Basra. According to historian Hugh N. Kennedy, Ubayd Allah was "more hasty and given to the use of force than his father, but a man whose devotion to the Umayyad cause could not have been doubted". In 674 he crossed the Amu Darya and defeated the forces of the ruler of Bukhara in the first known invasion of the city by Muslim Arabs. After he was appointed governor of Basra soon afterwards, he also took several thousand Bukharan captives with him as slaves. Out of those slaves the Bukhariya military unit was formed. From at least 674 and 675, Ubayd Allah had coins struck in his name in Khurasan and Basra, respectively. They were based on Sasanian coinage and written in Pahlavi script. The mints were located in Basra, Darabjird, Maysan, Narmashir, Jayy and, to a lesser extent, Kufa. The latter was attached to Ubayd Allah's governorship in 679/680, giving him full control of Iraq.
Sources: en.wikipedia.org
It is a synthetic peptide analogue of growth hormone-releasing hormone. Four substitutions in its sequence make it more resistant to enzymatic degradation than the natural hormone. In the version carrying a drug affinity complex, the peptide binds albumin and remains in circulation for days.
No regulatory agency has approved CJC-1295 for clinical use. Human trials were conducted in the 2000s, but the development programme was discontinued before any marketing application succeeded. Material sold today is offered as a research chemical, and its purity depends on the supplier.
Sermorelin is an unmodified fragment of growth hormone-releasing hormone and is cleared quickly. CJC-1295 contains substitutions that resist breakdown, and the form with a drug affinity complex persists much longer. Both act at the same receptor but differ substantially in duration of action.
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.