lyophilisation raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
CJC-1295 belongs to a class of synthetic peptides modeled on growth hormone releasing hormone, a forty-four amino acid signal produced by the hypothalamus. The compound is built from the first twenty-nine residues of the natural sequence, with four substitutions introduced at positions 2, 8, 15 and 27. These changes were designed to slow enzymatic breakdown while preserving receptor activation. The result is a peptide that is shorter than native GHRH and considerably more resistant to ordinary clearance pathways in circulation.
Two related forms appear under the CJC-1295 name. The simpler analogue, commonly written as modified GRF(1-29), carries the four substitutions but no additional conjugation. The second form attaches a maleimidopropionic acid linker to a lysine residue, a modification frequently called the drug affinity complex. That linker reacts with the free thiol on serum albumin to form a covalent bond. Because albumin has a long residence time in blood, the conjugated peptide stays in circulation far longer than the unconjugated analogue.
Receptor level activity follows the canonical GHRH pathway. The peptide binds the GHRH receptor, a class B G protein coupled receptor on somatotroph cells of the anterior pituitary. Binding raises intracellular cyclic AMP, which promotes calcium entry and the release of growth hormone into the bloodstream. Because the molecule acts at the same receptor as the endogenous hormone, its effect is superimposed on the natural pulsatile rhythm rather than replacing it. Whether sustained receptor occupation leads to desensitization is not fully settled.
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.
| Property | Value | Notes |
|---|---|---|
| Peptide class | Synthetic GHRH analogue | Built on a 29 residue sequence |
| Primary target | GHRH receptor (GHRHR) | Class B G protein coupled receptor |
| Unconjugated half life | Minutes | Limited by protease degradation |
| Key modification | Four residue substitutions | Positions 2, 8, 15 and 27 |
| Common synonym | Modified GRF(1-29) | Usually denotes the form without DAC |
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.
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.
== History == Deslorelin was successfully trialed in the U.S. and was approved for veterinary use under certain circumstances. In Europe, it was approved for use in equine assisted reproduction. Ovuplant was withdrawn from the U.S. market following issues with mares which did not become pregnant failing to return to estrus in a timely manner. Techniques were developed where the implant was removed 48 hours after implantation in the mare, however compounded biorelease Deslorelin products were at the time available as well as more commonly used ovulation promoters such as hCG, which did not produce the same failure effect. Upon "Sucromate Equine" receiving FDA-approval, the compounded products were no longer legally available within the U.S., however they remain available in Australia and New Zealand where an approved version is marketed. It is also being trialed in humans to study its efficacy in treatment of breast cancer in women, and in treating precocious puberty and congenital adrenal hyperplasia in male and female children. As of August 2011 this drug was not approved for general use outside the FDA-licensed functions in the U.S., other than within approved clinical trials. Orphan drug status has been designated in the U.S., though approval had not been issued as of 2011.
In 2010, Ian Read was named CEO. In February 2011, Pfizer announced the closure of its UK research and development facility (formerly also a manufacturing plant) in Sandwich, Kent, which at the time employed 2,400 people. In March 2011, Pfizer acquired King Pharmaceuticals for $3.6 billion in cash. King produced emergency injectables such as the EpiPen. On September 4, 2012, the FDA approved bosutinib (Bosulif) for chronic myelogenous leukemia (CML), a rare type of leukemia and a blood and bone marrow disease that affects primarily older adults. In November 2012, Pfizer received approval from the Food and Drug Administration for Xeljanz, a tofacitinib, for rheumatoid arthritis and ulcerative colitis. The drug had sales of $1.77 billion in 2018, and in January 2019, it was the top drug in the United States for direct-to-consumer advertising, passing adalimumab (Humira). In 2023, the Institute for Clinical and Economic Review (ICER) identified Xeljanz (tofacitinib) as one of five high-expenditure drugs that experienced significant net price increases without new clinical evidence to justify the hikes. Specifically, Xeljanz's wholesale acquisition cost rose by 6%, leading to an additional $72 million in costs to U.S. payers. On February 1, 2013, Zoetis, the Agriculture Division of Pfizer and later Pfizer Animal Health, became a public company via an initial public offering, raising $2.2 billion. Later in 2013, Pfizer completed the corporate spin-off of its remaining stake in Zoetis.
== WADA proscription == In 2015, Radwa Arafa Abd Elsalam, an athlete from Egypt, underwent a doping control where ractopamine was identified in the sample. Elsalam was sanctioned by the Egyptian Anti-Doping Organisation (EGY-NADO) with a two year ineligibility period for non-intentional presence of a prohibited substance, in violation of Article 2.1 of the EGY-NADO rules. While not mentioned by name in the 2015 Prohibited List, ractopamine was determined to — much like clenbuterol, another β2-adrenergic agonist — constitute an Other Anabolic Agent prohibited under S1.2. Elsalam appealed the decision, claiming that ractopamine is used in the meat industry overseas, so she must have inadvertently consumed food contaminated with ractopamine. EGY-NADO accepted her appeal, reduced the sanction to six months, and provided the World Anti-Doping Agency (WADA) with records pertaining to the case. WADA filed an appeal with the Court of Arbitration for Sport (CAS) against EGY-NADO and Elsalam with respect to the appealed decision. WADA asserted ractopamine was "undisputed[ly]" an Other Anabolic Agent, that "[i]t is not sufficient for an athlete merely to make protestations of innocence and suggest that the prohibited substance must have entered her body in inadvertently", and that "her explanations are nothing more than mere speculation".
=== 20 May === Eighteen Russian Shahed drones were launched at Kyiv. According to the Ukrainian Air Force all eighteen were shot down. Falling debris set fire to the roof of a residential complex in the Dniprovskyi District. This was the eleventh attack on the capital during the month of May. The Ukrainian Air Force also claimed to have destroyed two drones in the country's "east" and one in the "south" without further details. Yevgeny Prigozhin claimed on Telegram that his Wagner mercenaries had completely captured Bakhmut. This was denied by Ukraine, which nevertheless called the situation in the city "critical". The Russian Defence Ministry later confirmed the capture of the city, with President Putin sending his congratulations. Ukrainian President Volodymyr Zelenskyy met with Indian Prime Minister Narendra Modi at the G7 summit in Hiroshima for the first time since the Russian invasion of Ukraine. Pyotr Kucherenko, deputy science and higher education minister of the Russian Federation, suddenly fell ill on a plane returning from a business trip to Cuba. The aircraft landed at Mineralnye Vody however doctors were unable to save the minister's life. Kucherenko had reportedly called the war in Ukraine a "fascist invasion" in private. Exiled journalist Roman Super spoke to him "days before" his death, where Kucherenko expressed fears for his safety. The minister also had a preexisting heart condition.
Sources: en.wikipedia.org
Acid-catalyzed hydrolysis of esters is also an equilibrium process – essentially the reverse of the Fischer esterification reaction. Because an alcohol (which acts as the leaving group) and water (which acts as the nucleophile) have similar pKa values, the forward and reverse reactions compete with each other. As in transesterification, using a large excess of reactant (water) or removing one of the products (the alcohol) can promote the forward reaction.
As the power of the Roman Empire declined, the lands to the south and east of the Mediterranean Sea became incorporated into the Islamic Empires. Some Muslims believe hadiths, such as in Sahih Bukhari, prohibit every intoxicating substance, though the use of any intoxicant or substance is allowed as long as it is for medicinal purposes. Dioscorides' five-volume De Materia Medica, the precursor of pharmacopoeias, remained in use (which was edited and improved in the Arabic versions) from the 1st to 16th centuries, and described opium and the wide range of its uses prevalent in the ancient world.
ErythroMer is a red blood cell substitute in development by KaloCyte, supported with funding by the National Institutes of Health, U.S. Department of Defense, and private investment. Similar to other hemoglobin-based oxygen carriers, the product is stable for several months even when freeze-dried. It can be reconstituted from this lyophilized state in emergencies. This opens up the possibility of eventual stockpiling of ErythroMer, making it easier to supply blood in large amounts to those who need it. The development of this technology was done at Washington University in St. Louis and University of Illinois Urbana-Champaign. Trials have been successful in rats, mice, and rabbits, and human trials are planned. ErythroMer is a reddish blood powder composed of hemoglobin from humans. By coating it with a synthetic polymer, it can sense pH changes, allowing for oxygen pick up in areas where the pH levels are high and disposal where they are low. In the spring of 2024, ErythroMer showed promise in pre-clinical testing. In animal testing, it effectively delivered oxygen and helped revive animals with significant blood loss. In 2025, KaloCyte announced a licensing agreement with Chrysea for ErythroMer production.
=== Serotonin receptors === The serotonin receptors are located on the cell membrane of nerve cells and other cell types in animals, and mediate the effects of serotonin as the endogenous ligand and of a broad range of pharmaceutical and psychedelic drugs. There are currently 14 known serotonin receptors, including the serotonin 5-HT1 (1A, 1B, 1D, 1E, 1F), 5-HT2 (2A, 2B, 2C), 5-HT3, 5-HT4, 5-HT5 (5A, 5B), 5-HT6, and 5-HT7 receptors. Except for the serotonin 5-HT3 receptor, a ligand-gated ion channel, all other 5-HT receptors are G-protein-coupled receptors (also called seven-transmembrane, or heptahelical receptors) that activate an intracellular second messenger cascade. The 5-HT5B receptor is present in rodents but not in humans. In addition to the serotonin receptors, serotonin is an agonist of the trace amine-associated receptor 1 (TAAR1) in some species. It is a weak TAAR1 partial agonist in rats, but is inactive at the TAAR1 in mice and humans. The cryo-EM structures of the serotonin 5-HT2A receptor with serotonin, as well as with various serotonergic psychedelics, have been solved and published by Bryan L. Roth and colleagues.
=== Pneumatic elevator === A pneumatic elevator consists of a cylindrical vertical shaft (typically made of transparent plastic), and a passenger capsule (also transparent) within the shaft which moves vertically by means of differential air pressure above and below. The main advantage that it requires neither a pit below or a loft above the shaft. For ascending operations, a vacuum pump at the top of the elevator shaft creates a low pressure by drawing air from above the capsule while below the greater normal atmospheric pressure is permitted to enter at the lower (ground floor) level below the capsule providing lift. To descend, electronically controlled valves inside the tubular shaft regulate the entry and exit of air within the cylinder lowering the car smoothly by means of programmed operation. In the event of a failure of the vacuum pump or electronically controlled valves, the trapped volume of air below the capsule acts as a cushion that is allowed to slowly escape by means of a mechanical valve, gently returning the capsule to the lowest level.
Sources: en.wikipedia.org
== Legal status == Difenoxin is a Schedule I drug by itself in the US; the combination with atropine is in the less-restrictive category Schedule IV on account of the adulterant (the practice of making opioids more easily available by including an abuse-deterring adulterating agent is standard practice in the United States). Pure difenoxin, in Schedule I, has a quota of 50 grammes, and an ACSCN of 9168. The combination of difenoxin and atropine, in Schedule IV, has the DEA ACSCN of 9167 and being in Schedule IV is not assigned an aggregate annual manufacturing quota.
== History == When international vaccine care standards were being designed in the 1970s, the manuals typically generalized from the needs of care for the oral polio vaccine since that was the most delicate vaccine in wide use. In the 1970s PATH began working with the WHO to develop a system for identifying vaccines which had expired from improper storage. In 1996 the vaccine vial monitor was first used in a vaccine project, and by the next year it was widely accepted for use on many vaccine projects. It took until 2007 for VVMs to be widely adopted by vaccine manufacturers. by 2017, over 6.6 billion VVMs had been used. In 2007 in Geneva the World Health Organization hosted a commemoration in the presence of highly talented Antony Varghese and Augustin Shyju during the 10th anniversary of the introduction of VVMs. In 2007 PATH won a Tech Award for the development of the VVM.
Denbu (田麩), a food made by boiling powdered dried bonito flakes in sake and soy sauce, appears in an ancient 17th-century document called "Kokin Ryouri-shu" ("Collection of Ancient and Modern Cookbooks"). Tsukudani (佃煮), which appears in the 19th century colloquial dictionary "Risogonshuran" (俚言集覧) compiled by Ota Zensai (太田全斎), is made by boiling down small fish, shellfish, seaweed, and other ingredients in soy sauce to a rich flavor. The use of tsukudani is similar to furikake, but it is not usually called furikake in Japan today. The modern furikake was invented by several companies between the 1900s and 1920s for the purpose of tasty nourishment. Regarding modern furikake, the Japan Furikake Association recognized Futaba's "Gohan no Tomo" as the original in 1994, but revoked this recognition in 2022 and is conducting a reexamination. The association's conclusion has not been reached as of 2023. One account of the origin of furikake is that it was developed during the Taishō period (1912–1926) by a pharmacist in Kumamoto prefecture named Suekichi Yoshimaru (吉丸末吉). To address calcium deficiency in the Japanese population, Yoshimaru developed a mixture of ground fish bones with roast sesame seeds, poppy seeds, and seaweed that was made into a powder. This product, which he called Gohan no Tomo (ご飯の友, 'A Friend for Rice'), is generally considered the precursor to contemporary furikake. A food company in Kumamoto later acquired the product and was able to sell it commercially.
==== Polymers ==== Electronic components that require clear transparency for light to exit or enter (photovoltaic panels and sensors) can be potted using acrylic resins that are cured using UV energy. The advantages are low VOC emissions and rapid curing.
Sources: en.wikipedia.org
The names are often used interchangeably in casual writing, but they are not strictly identical. Modified GRF(1-29) refers to the unconjugated analogue carrying only the four substitutions. The version sold as CJC-1295 with DAC includes the albumin binding linker and clears much more slowly.
DAC stands for drug affinity complex, a term describing the maleimidopropionic acid linker. This group forms a covalent bond with the cysteine residue on serum albumin after administration. The resulting adduct is what extends the circulating half life from minutes to days.
No. It is entirely synthetic and does not correspond to any known endogenous peptide. The design starts from human growth hormone releasing hormone and introduces deliberate substitutions. Any biological effect comes from mimicking the natural hormone at its receptor.
No. It is a laboratory-synthesized analog built on a fragment of the natural hormone. The natural peptide is shorter-lived and lacks the stabilizing substitutions found in the synthetic version.