Everything below concerns deamidation. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-01-13. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Reverse-phase high-performance liquid chromatography is the standard method for purity assessment, separating the peptide from truncated or oxidized variants. Mass spectrometry confirms molecular mass and detects modifications, while ultraviolet absorbance near 280 nanometers supports concentration measurement through tryptophan and tyrosine residues. Circular dichroism can indicate secondary structure, though the peptide is largely helical in solution, and ion-exchange chromatography resolves charge variants. Purity values above 95 percent are typical for research-grade material. Stability studies track degradation over time under defined conditions.
Lyophilized semaglutide is typically stored at temperatures between minus 20 and minus 80 degrees Celsius for long-term preservation. Short-term storage at 2 to 8 degrees Celsius is common for working aliquots. Repeated freeze-thaw cycles can degrade the peptide and are usually avoided. The molecule is hygroscopic in its solid form, so containers should remain sealed with desiccant. Solutions are less stable than powders and are generally prepared fresh. Light exposure is limited because aromatic residues can undergo photo-oxidation.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white solid | typical of a lyophilised peptide preparation |
| Solubility behaviour | pH dependent | lowest near the isoelectric point |
| Storage of bulk material | Minus 20 degrees Celsius or below | protect from light and moisture |
| Storage of unused pen | 2 to 8 degrees Celsius | do not freeze |
| Common assay method | Reversed-phase HPLC | identity, purity and content |
== Plot == Jason sits on a bench in New York City waiting for someone to arrive. Jason's voiceover explains that he has been waiting for a long time, but to explain why, he needs to go back to the beginning. Jason tells the audience that every relationship reaches the "So..." moment, where someone in the relationship will want to take the relationship to a more serious place. At that point, Jason knows the relationship is over, as he is not ready for a serious relationship. Jason works with his best friend Daniel at a publishing house designing book covers. Their doctor friend Mikey, who has been married since the end of college, comes to them after his wife Vera requests a divorce. They decide to go out to a bar and celebrate Mikey now being single. The group meets up with Daniel's female wingman, Chelsea, as they try to get Mikey's mind off of his wife. Mikey meets a girl with glasses, while Jason meets Ellie, and hits it off with her after teasing another man that was trying to buy her a drink. Mikey gets "Glasses" number, but puts off calling her, resolving to work it out with Vera. Jason sleeps with Ellie, but leaves her apartment in a hurry after jumping to the mistaken conclusion that she is a prostitute. The next day, Jason and Daniel make a book cover pitch to a new author, who happens to be Ellie. Ellie is hurt and enraged that he did not stay the whole night. Jason tries to make it up to her, but she refuses. Jason, Daniel and Mikey then make a pact to stay single together for the foreseeable future.
in respect of the meridians (经络辩证; jīngluò biàn zhèng) in respect of qi (气血辩证,; qì xuè biàn zhèng) in respect of xuè (气血辩证; qì xuè biàn zhèng) in respect of the body fluids (津液辩证; jīnyè biàn zhèng) in respect of the zàng-fǔ (脏腑辩证; zàngfǔ biàn zhèng) – very similar to this, though less specific, is disharmony pattern description in terms of the Five Elements [五行辩证; wǔ xíng biàn zhèng]) There are also three special pattern diagnosis systems used in case of febrile and infectious diseases only ("Six Channel system" or "six division pattern" [六经辩证; liù jīng biàn zhèng]; "Wei Qi Ying Xue system" or "four division pattern" [卫气营血辩证; weì qì yíng xuè biàn zhèng]; "San Jiao system" or "three burners pattern" [三焦辩证; sānjiaō biàn zhèng]).
Basil I (r. 867–886) continued Michael's policies. His armies campaigned with mixed results in Italy but defeated the Paulicians of Tephrike. His successor Leo VI (r. 886–912) sponsored, compiled, and issued a large body of written works. These included the Basilika, a Greek translation of Justinian I's legal corpus that incorporated Leo's new laws; the Tactica, a military treatise; and the Book of the Eparch, a manual on Constantinople's trading regulations. Outside these literary, legal, and administrative projects, Leo's reign was less successful: the empire was defeated by the Bulgarians and lost Taormina, its last outpost on Sicily. He also provoked theological scandal by marrying four times in an attempt to father a legitimate heir. The early reign of this heir, Constantine VII, was tumultuous, as his mother Zoe, his uncle Alexander, the patriarch Nicholas, members of leading aristocratic families, and the powerful external pressure of Simeon I of Bulgaria shaped the struggle for power. In 920, the admiral Romanos I used his fleet to secure power, crowning himself and demoting Constantine to the position of junior co-emperor. His reign, marked by the end of the war against Bulgaria and successes in the east under the general John Kourkouas, ended in 944 when his sons deposed him; Constantine then removed them and ruled as sole emperor. Constantine's politically limited sole rule is often associated with the Macedonian Renaissance, but many of the works compiled at his court were also intended to legitimise and glorify the Macedonian dynasty.
Although francium is the heaviest alkali metal that has been discovered, there has been some theoretical work predicting the physical and chemical characteristics of hypothetical heavier alkali metals. Being the first period 8 element, the undiscovered element ununennium (element 119) is predicted to be the next alkali metal after francium and behave much like their lighter congeners; however, it is also predicted to differ from the lighter alkali metals in some properties. Its chemistry is predicted to be closer to that of potassium or rubidium instead of caesium or francium. This is unusual as periodic trends, ignoring relativistic effects would predict ununennium to be even more reactive than caesium and francium. This lowered reactivity is due to the relativistic stabilisation of ununennium's valence electron, increasing ununennium's first ionisation energy and decreasing the metallic and ionic radii; this effect is already seen for francium. This assumes that ununennium will behave chemically as an alkali metal, which, although likely, may not be true due to relativistic effects. The relativistic stabilisation of the 8s orbital also increases ununennium's electron affinity far beyond that of caesium and francium; indeed, ununennium is expected to have an electron affinity higher than all the alkali metals lighter than it. Relativistic effects also cause a very large drop in the polarisability of ununennium.
=== Peroxisome === There are two types of target peptides directing to peroxisome, which are called peroxisomal targeting signals (PTS). One is PTS1, which is made of three amino acids on the C-terminus. The other is PTS2, which is made of a 9-amino-acid sequence often present on the N-terminus of the protein.
Sources: en.wikipedia.org
=== Breast cancer === Anastrozole is used in the treatment and prevention of breast cancer in women. The Arimidex, Tamoxifen, Alone or in Combination (ATAC) trial was of localized breast cancer and women received either anastrozole, the selective estrogen receptor modulator tamoxifen, or both for five years, followed by five years of follow-up. After more than 5 years the group that received anastrozole had better results than the tamoxifen group. The trial suggested that anastrozole is the preferred medical therapy for postmenopausal women with localized estrogen receptor-positive breast cancer.
Outraging public decency is a common law offence in England and Wales, Hong Kong and the Australian states of New South Wales and Victoria. It is punishable by unlimited imprisonment and/or an unlimited fine. But in Hong Kong, as a common law offence, offenders can only be imprisoned for 7 years at maximum.
=== Tangren === Among some Southern Han Chinese varieties such as Cantonese, Hakka and Minnan, the term Tangren (唐人; Tángrén; 'people of Tang'), derived from the name of the later Tang dynasty (618–907) that oversaw what is regarded as another golden age of China. The self-identification as Tangren is popular in south China, because it was at this time that massive waves of migration and settlement led to a shift in the center of gravity of the Chinese nation, away from the tumult of the Central Plains to the peaceful lands south of the Yangtze and on the southeastern coast. This led to the earnest settlement by Chinese of lands previously regarded as part of the empire's sparsely populated frontier or periphery. Guangdong and Fujian, hitherto regarded as backwater regions, were populated by the descendants of garrison soldiers, exiles and refugees, became new centers and representatives of Han Chinese culture under the influence of the new Han migrants. The term is used in everyday colloquial discourse and is also an element in one of the words for Chinatown: 'streets of Tang people' (唐人街; Tángrénjiē; Tong4 jan4 gaai1). The phrase Huábù (華埠; 华埠) is also used to refer to Chinatowns.
From 2002 to 2004, Pinhasov carried out postdoctoral research at Johnson & Johnson Pharmaceutical Research and Development (Spring House, Pennsylvania, United States), where under the guidance of Dr. Douglas Brenneman he was engaged in the development of drugs for the treatment of neurodegenerative diseases. In 2005, Pinhasov joined the Department of Molecular Biology at Ariel University (formerly the College of Judea and Samaria) as an assistant professor. He was Head of the department from 2008 to 2014. In 2014, Pinhasov was appointed Vice-President and Dean of Research & Development at Ariel University, holding this position until 2020. In 2020 the Senate of Ariel University elected Professor Pinhasov as the Rector of Ariel University, succeeding Professor Michael Zinigrad, who held this office for 12 years. In September 2023, in recognition of his contribution to academic ties between Israel and Kazakhstan, the Senate of Astana Medical University (AMU) awarded Prof. Albert Pinhasov the title of honorary professor.
Sources: en.wikipedia.org
== Academics and science == Mark C. Alexander, law professor at Seton Hall University Buzz Aldrin (born 1930), astronaut, who was the second man to walk on the Moon Virginia Lee Block (1902–1970), psychologist who contributed to studies regarding child and adolescent psychology Stella Stevens Bradford (1871–1959), doctor, specialist in tuberculosis and physical rehabilitation H. Bruce Franklin (1934–2024), author and historian who was expelled from his Stanford University professorship for involvement in a leftist group Tom Galligan (born 1955), lawyer, legal scholar, administrator, and educator who is currently the dean and professor of law of Louisiana State University's Paul M. Hebert Law Center Dean Hamer (born 1952), scientist, author, and filmmaker who discovered a link between sexual orientation and Xq28 Jordan Harrod (born 1996), research scientist and YouTuber who works on neuroengineering, brain-machine interfaces, and machine learning for medicine George Rice Hovey (1860–1943), university president, professor, minister, and author who served as the president of Virginia Union University from 1904 to 1918 John A. Kenney Jr. (1914–2003), pioneering African-American dermatologist who specialized in the study of skin disorders affecting racial minorities, earning him recognition as the "dean of black dermatology" Joshua Lederberg (1925–2008), geneticist who received the 1958 Nobel Prize in Physiology or Medicine for work in bacterial genetics; born in Montclair Ronald T.
=== GLP-1 weight loss entry and Super Bowl advertising (2024–2025) === In May 2024, Hims & Hers began offering access to compounded injectable semaglutide, a glucagon-like peptide-1 receptor agonist (GLP-1) prescription treatment, as part of a new weight-loss specialty on its platform. The move followed a national shortage of branded semaglutide products Ozempic and Wegovy made by Novo Nordisk, which allowed Section 503A compounding pharmacies and 503B outsourcing facilities to legally produce copies of the drug. In September 2024, the company acquired MedisourceRx, a licensed 503B compounding outsourcing facility, to vertically integrate its compounded medicine supply chain. In February 2025, Hims & Hers aired a 60-second commercial titled "Sick of the System" during Super Bowl LIX on Fox, the first Super Bowl advertisement to promote GLP-1 weight loss treatments. The advertisement drew criticism from public health experts, industry trade groups and members of the United States Congress for framing the compounded semaglutide products as a solution to the American obesity epidemic without disclosing side-effect or risk information. Senators Dick Durbin and Roger Marshall wrote a joint letter to the Food and Drug Administration urging enforcement action.
4 RSeOH → 2 RSe(O)SeR + 2 H2O Even the very bulky 2,4,6-tri-tert-butylbenzeneselenenic acid disproportionates readily. Stable selenenic acids have been synthesized by burying the SeOH functional group within the cavity of a p-tert-butyl[calix[6]arene macrocycle]. In BmtSeOH (pictured), the Se-O bond length was found to be 1.808 Å while the O-Se-C angle was 96.90°. The compound was made by oxidation of BmtSeH; further oxidation gave BmtSeO2H. The Se-O absorbs in the IR spectrum at 680–700 cm−1. Selenenic acids are believed to be transient intermediates in a number of redox reactions involving organoselenium compounds. One notable example is the syn-elimination of selenoxides. Selenenic acids are also transient intermediates in the reduction of seleninic acids as well as the oxidation of diselenides. The reasoning for postulating selenenic acids as reactive intermediates is based in part on analogy with their more extensively studied sulfenic acid analogs.
Transmucosal (diffusion through a mucous membrane), e.g. insufflation (snorting) of cocaine, sublingual, i.e. under the tongue, sublabial, i.e. between the lips and gingiva, and oral spray or vaginal suppository for nitroglycerine.
As the nascent polypeptide elongates during proteosynthesis, it passes through the ribosomal tunnel, interacting with the tunnel walls, thus regulating the rate at which it passes through the tunnel. This in turn affect the rate of partial folding, which may already occur at this stage. Short stretches of alpha-helix may form in the inner part of the tunnel and tertiary structure may start forming in the wider tunnel vestibule. As the N-terminus reaches the tunnel exit and is processed by the ribosome-associated protein biogenesis factors, the tertiary structure formed in the tunnel may partially refold. The folding is then completed when the C-terminus is released from the PTC and the protein escapes the tunnel.
Sources: en.wikipedia.org
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.
Size-exclusion chromatography is the most common technique, separating monomer from dimer and higher-order species by hydrodynamic volume. It is usually paired with ultraviolet detection and, for trace work, with multi-angle light scattering. Results depend on mobile-phase conditions, so method details matter when comparing datasets.
The detailed degradation profile under real-world temperature excursions and repeated handling is not fully described in the open literature. Relative contributions of photo-degradation versus thermal pathways are also incompletely mapped. Whether specific impurity species carry different biological activity is an open question rather than an established finding.
Long-term storage is usually at minus 20 to minus 80 degrees Celsius in a sealed, desiccated container. Working aliquots can be held briefly at 2 to 8 degrees Celsius.