If you have been reading about lyophilized powder 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.
Last reviewed on 2026-05-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
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.
| 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 |
At the pituitary, the peptide binds the growth hormone-releasing hormone receptor on somatotroph cells. Receptor activation raises intracellular cyclic AMP and triggers release of stored growth hormone. Somatostatin and other hypothalamic signals modulate this response. Negative feedback from insulin-like growth factor 1 also influences output. The same regulatory architecture operates with the native hormone. Whether the synthetic analog alters feedback dynamics over repeated exposure remains an open question. Most published receptor work uses cell models rather than intact human systems.
CJC-1295 is a synthetic peptide belonging to the growth hormone-releasing hormone analog family. It comprises twenty-nine amino acid residues derived from the N-terminal region of natural GHRH. The molecule incorporates several non-natural substitutions that increase resistance to enzymatic degradation. These modifications extend its activity compared with the native hormone fragment. Researchers use it to study pituitary growth hormone secretion in laboratory and clinical settings. This compound is distinct from native GHRH in its stability profile.
Lyophilized material is generally stable for extended periods when held at minus twenty degrees Celsius or below and protected from moisture and light. In solution the peptide is more labile; bond hydrolysis, aggregation and oxidation of susceptible residues all proceed faster at ambient temperature. Repeated freeze and thaw cycles should be avoided because they promote clumping and loss of soluble material. The conjugated variant adds a further consideration, since the maleimide group can hydrolyze in aqueous buffer and lose its ability to react with albumin.
Laboratory handling centers on minimizing exposure to water, heat and oxygen before use. Working solutions are typically prepared in sterile water or a mild buffer, and any residual particulate matter is removed by filtration. When the powder dissolves slowly, a small proportion of acetonitrile or dilute acetic acid is sometimes added as a co-solvent. Containers are kept sealed and desiccated between uses. Records of lot number, reconstitution date and storage conditions support later comparison of results across experiments.
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.
==== Carbon ==== Stable isotope analysis of carbon in human bone collagen allows bioarchaeologists to carry out dietary reconstruction and to make nutritional inferences. These chemical signatures reflect long-term dietary patterns, rather than a single meal or feast. Isotope ratios in food, especially plant food, are directly and predictably reflected in bone chemistry, allowing researchers to partially reconstruct recent diet using stable isotopes as tracers. Stable isotope analysis monitors the ratio of carbon 13 to carbon 12 (13C/12C), which is expressed as parts per thousand using delta notation (δ13C). The 13C and 12C ratio is either depleted (more negative) or enriched (more positive) relative to a standard. 12C and 13C occur in a ratio of approximately 98.9 to 1.1.
In May 2002, The Bill & Melinda Gates Foundation purchased stock in Merck. From 2002 through 2005, the Australian affiliate of Merck paid publishing house Elsevier an undisclosed amount to produce eight issues of a medical journal, the Australasian Journal of Bone and Joint Medicine. Although it gave the appearance of being an independent peer-reviewed journal, without any indication that Merck had paid for it, the journal actually reprinted articles that originally appeared in other publications and that were favorable to Merck. The misleading publication came to light in 2009 during a personal injury lawsuit filed over Vioxx; 9 of 29 articles in the journal's second issue referred positively to Vioxx. The CEO of Elsevier's Health Sciences Division, Michael Hansen, admitted that the practice was "unacceptable". Elsevier initially said that it compiled reprinted articles and it did not consider such compilation a journal. It was later forced to retreat and apologize. In 2005, Gilmartin retired as CEO following Merck's voluntary worldwide withdrawal of Vioxx. Gilmartin's tenure was criticized as abandoning Vagelos' commitment to corporate social responsibility. Former president of manufacturing Richard Clark was named CEO and company president. In November 2009, Merck & Co. completed a merger with Schering-Plough in a US$41 billion deal. Although Merck & Co. was in reality acquiring Schering-Plough, the purchase was declared a "reverse merger", in which "Old" Merck & Co.
==== United States ==== In the United States, tianeptine is not considered by the Drug Enforcement Administration as a controlled substance or analogue thereof. However, its use in dietary supplements and food is unlawful. The Food and Drug Administration (FDA) has issued warnings, as recently as January 2024, about the dangers of recreational tianeptine use and the risks posed by adulterated dietary supplements containing undeclared tianeptine. On 6 April 2018, Michigan became the first US state to outlaw tianeptine sodium, classifying it as a schedule II controlled substance. The scheduling of tianeptine sodium is effective 4 July 2018. On 1 November 2019, Tianeptine became a Schedule II controlled dangerous substance as classified within the Uniform Controlled Dangerous Substances Act of the state of Oklahoma. On 15 March 2021, Alabama outlawed tianeptine, initially classifying it as a schedule II controlled substance. It was later reclassified as a schedule I controlled substance on 14 November 2021. On 1 July 2022, Tennessee outlawed tianeptine and adds "any salt, sulfate, free acid, or other preparation of tianeptine, and any salt, sulfate, free acid, compound, derivative, precursor, or preparation thereof that is substantially chemically equivalent or identical with tianeptine", classifying it as a schedule II controlled substance. On 22 December 2022, Ohio outlawed tianeptine, classifying it as a schedule I controlled substance with Ohio Governor Mike DeWine referencing the widespread availability of the chemical there as "gas-station heroin".
Both sides also agreed to establish communication channels for AI-related issues. The US welcomes the arrival of the pair of giant pandas loaned by China to the Atlanta Zoo. The two countries also agreed to sign a memorandum of understanding as soon as possible to strengthen crisis communication and prevention, and to continue to cooperate in the search for the remains of missing US military personnel in China. The US announced that the reduced tariffs on $30 billion of non-sensitive goods from each side would including agricultural goods, wood and cosmetics, as well as US imports such as small appliances, toys, decorations. The US also said China agreed to import 10 million tons of coals from the US in 2027 and 2028. Chinese foreign minister Wang Yi said that Xi's visit to the United States "further expanded the connotation of the new positioning of China–US relations", clearly defined respect, fairness and equality, and at the same time "provided clearer strategic guidance for China and the United States to explore the way of major powers getting along". He said that "It means the two countries have equal sovereignty and no one is more superior than the other. None is domineering or abusive and they should resolve their own concerns on an equal footing". Wang also said that Peng Liyuan and Melania Trump's interactions "brought the hearts of the two peoples closer" and that "Warm and personable first-lady diplomacy has injected a softer force into the visit".
Sources: en.wikipedia.org
== Product development == The company's operations are divided into three segments: Custom Manufacturing Solutions, which develops APIs from pre-clinical to commercial stages; Generic Drug Substances, which manufactures non-exclusive APIs; and a Peptide API unit that specializes in peptide synthesis.
Smoking of opium came on the heels of tobacco smoking and may have been encouraged by a brief ban on the smoking of tobacco by the Ming emperor. The prohibition ended in 1644 with the coming of the Qing dynasty, which encouraged smokers to mix in increasing amounts of opium. In 1705, Wang Shizhen wrote: "nowadays, from nobility and gentlemen down to slaves and women, all are addicted to tobacco". Tobacco in that time was frequently mixed with other herbs (this continues with clove cigarettes to the modern day), and opium was one component in the mixture. Tobacco mixed with opium was called madak (or madat) and became popular throughout China and its seafaring trade partners (such as Taiwan, Java, and the Philippines) in the 17th century. In 1712, Engelbert Kaempfer described addiction to madak: "No commodity throughout the Indies is retailed with greater profit by the Batavians than opium, which [its] users cannot do without, nor can they come by it except it be brought by the ships of the Batavians from Bengal and Coromandel." Fueled in part by the 1729 ban on madak, which at first effectively exempted pure opium as a potentially medicinal product, the smoking of pure opium became more popular in the 18th century. In 1736, the smoking of pure opium was described by Huang Shujing, involving a pipe made from bamboo rimmed with silver, stuffed with palm slices and hair, fed by a clay bowl in which a globule of molten opium was held over the flame of an oil lamp.
== Medical uses == Daunorubicin/cytarabine is indicated for the treatment of newly-diagnosed therapy-related acute myeloid leukemia (t-AML) or AML with myelodysplasia-related changes (AML-MRC) in people aged one year of age and older.
== Factors that affect BV == The determination of BV is carefully designed to accurately measure some aspects of protein usage whilst eliminating variation from other aspects. When using the test (or considering BV values) care must be taken to ensure the variable of interest is quantified by BV. Factors which affect BV can be grouped into properties of the protein source and properties of the species or individual consuming the protein.
== Undeveloped variants == Only the base version of the Il-86 and a small batch of military derivatives entered service. Further versions were mooted but none entered service. Freight or combined passenger-freight versions are not known to have been proposed.
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.
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.