Everything below concerns purity. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-08-09. Where a claim depends on a specific study, the study is described rather than over-claimed.
Pharmacological activity arises from agonism at the glucagon-like peptide-1 receptor, a G protein-coupled receptor expressed in the pancreas, the gastrointestinal tract, and the brainstem. Receptor activation raises intracellular cyclic adenosine monophosphate and enhances insulin release in a glucose-dependent manner, an effect that diminishes when blood glucose concentration is low. Other effects include slowed gastric emptying and hypothalamic satiety signalling. These pathways are described well. Receptor desensitisation rates across tissues, relative to the endogenous hormone, are still under investigation, and reported findings differ between laboratories.
The company that developed the compound filed it as a long-acting analogue, and it gained first approval in 2017 for type 2 diabetes. Later authorisations from several regulators extended the indication to chronic weight management, and the World Health Organization added the glucagon-like peptide-1 receptor agonist drug class to its model list of essential medicines in 2023. Production uses solid-phase peptide synthesis followed by side-chain conjugation and chromatographic purification. Supply constraints and cost differences across regions are well documented. Literature on long-term outcomes continues to grow, with many trials reporting surrogate endpoints rather than hard clinical endpoints.
Semaglutide is a synthetic peptide of thirty-one amino acids that shares roughly ninety-four percent sequence identity with human glucagon-like peptide-1. Two substitutions resist enzymatic cleavage by dipeptidyl peptidase-4, and a fatty diacid side chain attached through a linker promotes binding to serum albumin. That albumin binding slows renal clearance and extends the circulating half-life from minutes to approximately one week. The structural changes are well established in the published literature. Whether the same modifications affect receptor signalling bias in ways that matter clinically remains an open question.
Quantification and purity assessment rely on separation methods coupled to optical or mass detection. Reversed-phase high-performance liquid chromatography resolves the intact peptide from related impurities and is the standard assay technique. Size-exclusion chromatography measures aggregates, while ion-exchange chromatography separates charge variants produced by deamidation. Mass spectrometry confirms identity and detects mass shifts of a few daltons. In biological matrices, liquid chromatography with tandem mass spectrometry is often used because immunoassays can cross-react with endogenous GLP-1 or with circulating fragments.
As a peptide, semaglutide is sensitive to conditions that break amide bonds or modify side chains. Deamidation of asparagine and glutamine residues, oxidation of methionine and tryptophan, and non-covalent aggregation are the main degradation routes described in published stability work. Rate depends strongly on pH, buffer species, ionic strength, temperature and exposure to light. Formulators therefore choose a defined solution pH and often add excipients such as phosphate buffer, propylene glycol and phenol, each of which plays a separate role in pH control, tonicity or preservation.
Storage guidance for the finished injectable product distinguishes the unused state from the in-use state. Before first use, pens are kept refrigerated between 2 and 8 degrees Celsius, protected from light, and never frozen, since freezing can disrupt the peptide or the device. After first use, label instructions in several markets permit storage at room temperature up to about 30 degrees Celsius for a limited number of days. Solid research-grade material is normally held at or below minus 20 degrees Celsius, often with desiccant, and allowed to equilibrate before opening.
| Property | Value | Notes |
|---|---|---|
| Molecular class | 31-amino-acid peptide | Modified glucagon-like peptide-1 analogue |
| Molecular mass | approximately 4114 Da | Calculated for the free peptide backbone |
| Appearance | white to off-white powder | Typical of purified lyophilised peptide batches |
| Solubility class | freely soluble in water | Aqueous solubility improves at slightly alkaline pH |
| Typical storage | -20 degrees Celsius, dry, dark | Protect from repeated freeze-thaw cycles |
Receptor activation follows the canonical Gs pathway: binding increases intracellular cyclic AMP, which promotes protein kinase A activity. In pancreatic beta cells this amplifies glucose-dependent insulin release, so secretion rises when blood glucose is high and changes little when it is low. The same signalling suppresses glucagon release from alpha cells and slows gastric emptying. Receptors in the hypothalamus and brainstem are thought to contribute to reduced appetite and lower energy intake. Which of these effects dominates clinical outcomes remains an area of active study.
Semaglutide is a synthetic peptide analogue of glucagon-like peptide-1, a gut hormone released by intestinal L cells after food intake. The natural hormone acts on pancreatic and central receptors but is degraded within minutes by dipeptidyl peptidase-4 and other peptidases. Semaglutide belongs to the class of long-acting GLP-1 receptor agonists, a group distinguished by structural changes that slow breakdown and extend circulation time. Its development followed earlier short-acting analogues and reflects a general strategy in peptide drug design: preserve receptor activity while blocking proteolytic clearance.
Certificate of analysis documents from suppliers typically report purity by chromatographic area, water content, and counter-ion identity. Independent verification is advisable because reported values can be generated under differing conditions. Impurity profiles matter for research use, where aggregates, deamidation products, and residual solvents may influence experimental results. Container, lot, and chain-of-custody records support traceability. Analytical results are method-dependent, so comparisons between laboratories require the same procedure and reference standards.
Lyophilized peptide material is typically stored at or below -20 °C, with -80 °C used for longer-term archives. Vials should remain sealed and desiccated because moisture promotes aggregation and hydrolysis. Repeated freeze-thaw cycles are avoided since they can alter peptide conformation and reduce recovery. Once reconstituted, solutions are generally kept at 2-8 °C and used within a defined window. Stability beyond those windows depends on buffer composition and concentration, and exact limits are product-specific rather than universal.
Identity and purity are assessed with reversed-phase high-performance liquid chromatography, which separates the peptide from related impurities by hydrophobicity. Mass spectrometry confirms molecular weight and detects truncation or modification products. Peptide mapping after enzymatic digestion verifies the amino acid sequence. Quantitation is often performed by LC-MS/MS or by immunoassay, and the two approaches can give different values because they measure different things. Method validation parameters such as accuracy, precision, and limit of quantitation are reported alongside results.
Two structural features account for the prolonged half-life of semaglutide. A modified amino acid at position 8 resists cleavage by dipeptidyl peptidase-4, the enzyme that rapidly degrades native GLP-1. A fatty diacid side chain binds serum albumin, which limits renal clearance and protects the peptide from enzymatic breakdown. These modifications yield a plasma half-life of approximately one week in humans, allowing once-weekly administration. The relationship between plasma concentration and clinical effect varies between individuals, and sources of that variability are still being characterized.
Semaglutide is a synthetic peptide analog of glucagon-like peptide-1 (GLP-1), a hormone released from intestinal L-cells after food intake. The compound belongs to the incretin mimetic class and acts at GLP-1 receptors distributed across pancreatic, gastrointestinal, cardiovascular, and central nervous system tissues. Compared with native GLP-1, the molecule carries structural changes that extend its activity from minutes to roughly one week. It is studied for glycemic control in type 2 diabetes and for weight management, and its effects on cardiovascular and other outcomes remain active research areas.
Receptor binding triggers G protein signaling that raises intracellular cyclic AMP in pancreatic beta cells. Insulin release follows in a glucose-dependent manner, so secretion increases when blood glucose is elevated and diminishes when it is not. The same signaling suppresses glucagon release from alpha cells and slows gastric emptying, which blunts the post-meal glucose rise. In the brain, receptor activation in regions such as the arcuate nucleus is associated with reduced appetite and lower energy intake. How much each of these effects contributes to overall weight change is not fully settled.
For example, they are known to use both wine and raki in their ceremonial meetings, and were not known, in earlier times, to have observed the fast of Ramadan or the obligation of five daily prayer times. (ref: "Conforming Haji Bektash: A Saint and His Followers between Orthopraxy and Heteropraxy"; Mark Soileau, Die Welt des Islams 54 (2014) 423-459) Bektashis follow the modern-day Bektashi Dedebabate, currently headed by Baba Mondi. Bektashis consider the Dedebaba as leader over the entire branch. Bektashism is also heavily permeated with Shia Islamic concepts, such as the marked reverence of Ali, the Twelve Imams, and the ritual commemoration of Ashura marking the Battle of Karbala. The old Persian holiday of Nowruz is celebrated by Bektashis as Ali's birthday (see also Nevruz in Albania). The Bektashi order is a Sufi order and shares much in common with other Islamic mystical movements, such as the need for an experienced spiritual guide—called a baba in Bektashi parlance—as well as the Sufi doctrine of "the four gates that must be traversed": Sharī'a (religious law), Ṭarīqa (the spiritual path), Ma'rifa (true knowledge), and Ḥaqīqa (truth). There are many other practices and ceremonies that share similarities with other faiths, such as a ritual meal (muhabbet) and yearly confession of sins to a baba (magfirat-i zunub مغفرة الذنوب). Bektashis base their practices and rituals on their non-orthodox and mystical interpretation and understanding of the Quran and the prophetic practice (Sunnah).
==== Administration, economy and technology ==== Local Administration and Development Committee Investment, Reconstruction and Sustainable Development Committee Public Ports and Customs Committee Communications, Digital Transformation and Information Technology Committee
Minnich, V.; Na-Nakorn, S.; Chong-Chareonsuk, S.; Kochaseni, S. (January 1954). "Mediterranean anemia; a study of thirty-two cases in Thailand". Blood. 9 (1): 1–23. doi:10.1182/blood.V9.1.1.1. ISSN 0006-4971. PMID 13115468. Chernoff, Amoz I.; Minnich, Virginia; Chongchareonsuk, Soodsarkorn (1954). "Hemoglobin E, a Hereditary Abnormality of Human Hemoglobin". Science. 120 (3120): 605–606. Bibcode:1954Sci...120..605C. doi:10.1126/science.120.3120.605. JSTOR 1682300. PMID 13205193. Pica
==== United States ==== In the United States, mescaline was made illegal in 1970 by the Comprehensive Drug Abuse Prevention and Control Act, categorized as a Schedule I hallucinogen. The drug is prohibited internationally by the 1971 Convention on Psychotropic Substances. Mescaline is legal only for certain religious groups (such as the Native American Church by the American Indian Religious Freedom Act of 1978) and in scientific and medical research. In 1990, the Supreme Court ruled that the state of Oregon could ban the use of mescaline in Native American religious ceremonies. The Religious Freedom Restoration Act (RFRA) in 1993 allowed the use of peyote in religious ceremony, but in 1997, the Supreme Court ruled that the RFRA is unconstitutional when applied against states. Many states, including the state of Utah, have legalized peyote usage with "sincere religious intent", or within a religious organization, regardless of race. Synthetic mescaline, but not mescaline derived from cacti, was officially decriminalized in the state of Colorado by ballot measure Proposition 122 in November 2022. While mescaline-containing cacti of the genus Echinopsis are technically controlled substances under the Controlled Substances Act, they are commonly sold publicly as ornamental plants.
Several different types of interferons are approved for use in humans. One was first approved for medical use in 1986. For example, in January 2001, the Food and Drug Administration (FDA) approved the use of PEGylated interferon-alpha in the USA; in this formulation, PEGylated interferon-alpha-2b (Pegintron), polyethylene glycol is linked to the interferon molecule to make the interferon last longer in the body. Approval for PEGylated interferon-alpha-2a (Pegasys) followed in October 2002. These PEGylated drugs are injected once weekly, rather than administering two or three times per week, as is necessary for conventional interferon-alpha. When used with the antiviral drug ribavirin, PEGylated interferon is effective in treatment of hepatitis C; at least 75% of people with hepatitis C genotypes 2 or 3 benefit from interferon treatment, although this is effective in less than 50% of people infected with genotype 1 (the more common form of hepatitis C virus in both the U.S. and Western Europe). Interferon-containing regimens may also include protease inhibitors such as boceprevir and telaprevir. There are also interferon-inducing drugs, notably tilorone that is shown to be effective against Ebola virus.
Sources: en.wikipedia.org
Abdominal pain Anxiety Panic attacks Depression Piloerection (goose bumps) Inability to enjoy daily activities Muscle and joint pain Nausea Vomiting Runny nose and excessive secretion of tears Sweating In the clinical setting, excessive secretion of tears, yawning, and dilation of pupils are helpful presentations in diagnosing opioid withdrawal. Hydromorphone is a rapid-acting painkiller; however, some formulations may last up to several hours. Patients who stop taking this drug abruptly may experience withdrawal symptoms, which may start within hours of taking the last dose of hydromorphone, and last up to several weeks. Withdrawal symptoms in people who stopped taking the opioid may be managed by using opioids or non-opioid adjuncts. Methadone is an opioid commonly used for this kind of therapy. However, the selection of therapy should be tailored to each specific person. Methadone also is used for detoxification in people who have opiate addiction, such as heroin or drugs similar to morphine. It may be given orally or intramuscularly. There is controversy regarding whether any opioid (such as methadone) should be included in the treatment of opioid withdrawal symptoms, since these agents also may cause relapse when therapy is suspended. Clonidine is a non-opioid adjunct which may be used in situations where opioid use is not desired, such as in patients with high blood pressure.
=== Plaque psoriasis === Adalimumab has been shown to treat moderate to severe chronic plaque psoriasis in adults who have the condition in many areas of their body and who may benefit from taking injections or pills (systemic therapy) or phototherapy (treatment using ultraviolet light alone or with pills). Adalimumab has been shown to be effective therapy when used either continuously or intermittently in patients with moderate to severe psoriasis.
=== Books === Separation Processes (1971); 2nd edition (1980) Freeze Drying of Foods (1971) The University of California: Creating, Nurturing, and Maintaining Academic Quality in a Public University Setting (2018)
The Turkish and Persian people were the first to cultivate tulips. While the cultivation of tulips in Iranian gardens dates back to the 10th century, the westward expansion of diverse tulip varieties into Asia Minor occurred most significantly under the Seljuk dynasty. The Persian poet Omar Khayyam's 11th-century poetry frequently featured the tulip as a symbol of ideal feminine beauty. Early cultivars must have emerged from hybridisation in gardens from wild collected plants, which were then favoured, possibly due to flower size or growth vigour. The tulip is not mentioned by any writer from antiquity, therefore it seems probable that tulips were introduced into Anatolia only with the advance of the Seljuks. In the Ottoman Empire, numerous types of tulips were cultivated and bred, and today, 14 species can still be found in Turkey. Tulips are mentioned by the 13th century Persian sufi mystic Jalāl ad-Dīn Rûmi. Species of tulips in Turkey typically come in red, less commonly in white or yellow. The Ottoman Turks had discovered that these wild tulips were great changelings, freely hybridising (though it takes 7 years to show colour) but also subject to mutations that produced spontaneous changes in form and colour. A paper by Arthur Baker reports that in 1574, Sultan Selim II ordered the Kadi of A'azāz in Syria to send him 50,000 tulip bulbs. However, John Harvey points out several problems with this source, and there is also the possibility that tulips and hyacinth (sümbüll), originally Indian spikenard (Nardostachys jatamansi) have been confused.
Oxytocin may aid romantically attached couples by increasing feelings of anxiety during separation. Group-serving dishonesty/deception: In a carefully controlled study exploring the biological roots of immoral behavior, oxytocin was shown to promote dishonesty when the outcome favored the group to which an individual belonged instead of just the individual. Oxytocin affects social distance between adult males and females, and may be responsible at least in part for romantic attraction and subsequent monogamous pair bonding. An oxytocin nasal spray caused men in a monogamous relationship, but not single men, to increase the distance between themselves and an attractive woman during a first encounter by 10 to 15 centimeters. The researchers suggested that oxytocin may help promote fidelity within monogamous relationships. For this reason, it is sometimes referred to as the "bonding hormone". There is some evidence that oxytocin promotes ethnocentric behavior, incorporating the trust and empathy of in-groups with their suspicion and rejection of outsiders. Furthermore, genetic differences in the oxytocin receptor gene (OXTR) have been associated with maladaptive social traits such as aggressive behavior. Social behavior and wound healing: Oxytocin is also thought to modulate inflammation by decreasing certain cytokines. Thus, the increased release in oxytocin following positive social interactions has the potential to improve wound healing. A study by Marazziti and colleagues used heterosexual couples to investigate this possibility.
Sources: en.wikipedia.org
One case of prophylactic delivery involving PLGA is for the antibiotic vancomycin, which is typically injected after brain surgery to prevent infections from bacteria including Staphylococcus aureus. Dental scaffolds and bone regeneration: PLGA has been used in periodontal and dental applications, specifically scaffolds and barrier membranes for bone and tissue regeneration. Cancer immunotherapy: PLGA has emerged as a platform for modulating tumors microenvironments. By encapsulating or conjugating drugs (ex: Doxorubicin) to PLGA, researchers try to overcome drug resistance and minimize cytotoxicity compared to free drug releases.
== Attenuation in eukaryotes == Although an attenuation mechanism that involves translation while transcription is ongoing, like to the mechanism for the trp operon (and some other amino acid biosynthetic operons), would not work in eukaryotes, there is evidence for attenuation in Eukaryotes. Research conducted on microRNA processing provides evidence of eukaryotic attenuation; after co-transcriptional endonucleolitical cleavage by Drosha 5'->3' exonuclease XRN2 may terminate further transcription by torpedo mechanism.
PDRN-based formulations – nucleotide-derived compounds used in cosmetic and skin health applications. TCI incorporates PDRN into its cosmetic and skin health formulation portfolio as part of its broader beauty-from-within and topical skincare product lines. A recognized challenge in cosmetic application of PDRN is its large molecular weight, susceptibility to decomposition, low bioavailability, and poor stability and skin permeability — factors that have spurred development of delivery technologies such as liposomal encapsulation. TCI's broader CDMO capabilities in liposomal formulation, marketed under the doubleNUTRI liposomal platform, are relevant to addressing such delivery challenges for bioactive ingredients. Happy Banana - Banana Peel Extract is a proprietary botanical ingredient developed by TCI from the peel of Musa × paradisiaca. The ingredient has been developed for applications related to sleep health, mood support, and circadian rhythm regulation. TCI has established extraction and standardization technologies and conducted both in vitro studies and randomized, double-blind, placebo-controlled human clinical trials to evaluate its physiological effects. According to published studies, supplementation with the ingredient was associated with changes in biomarkers related to serotonin, melatonin, autonomic nervous system activity, and sleep quality.The ingredient has also been included in a U.S.
"UNODC - Bulletin on Narcotics: The narcotic pepper - The chemistry and pharmacology of Piper methysticum and related species". United Nations Office on Drugs and Crime. 1973. pp. Issue 2. Retrieved 19 February 2014. Kava ban documents Piper methysticum information from the Hawaiian Ecosystems at Risk project (HEAR) "Kava" . Encyclopædia Britannica. Vol. 14 (9th ed.). 1882.
==== Efficacy ==== Several possible reasons for the variable efficacy of BCG in different countries have been proposed. None has been proven, some have been disproved, and none can explain the lack of efficacy in low tuberculosis-burden countries (US) and high tuberculosis-burden countries (India). The reasons for variable efficacy have been discussed at length in a WHO document on BCG.
Sources: en.wikipedia.org
It is a glucagon-like peptide-1 receptor agonist, often grouped with the incretin mimetics. Its backbone is modified from the human hormone to resist enzymatic degradation and to bind albumin. These two features distinguish it from the native peptide.
No. It shares high sequence identity but carries non-natural modifications that alter its stability and clearance. The naturally occurring hormone is broken down within minutes, while the synthetic analogue circulates far longer.
Attachment to serum albumin reduces renal filtration of the peptide and shields it from enzymatic breakdown. The consequence is a much longer interval between administrations than unmodified peptides allow. The precise contribution of binding affinity to overall duration is still being quantified.
Ice formation concentrates solutes and can mechanically stress the peptide or damage the delivery device. Thawing afterwards may leave aggregates that are not visible to the eye. Refrigeration keeps the solution above its freezing point while slowing chemical degradation.