The short version of deamidation fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-08-16. Anything still debated is marked as such rather than presented as settled.
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.
Semaglutide dissolves readily in water and in aqueous buffers near neutral pH. Solubility decreases near the isoelectric point, where net charge is minimal. Common laboratory solvents include phosphate-buffered saline and dilute ammonium bicarbonate. Strongly acidic or basic conditions may accelerate hydrolysis. Working concentrations are usually prepared by diluting a concentrated stock. Vial surfaces can adsorb small amounts of peptide at low concentrations, so carrier proteins or low-binding tubes are sometimes used.
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 |
|---|---|---|
| Appearance | White to off-white powder | Lyophilized form |
| Solubility | Water and aqueous buffers | Near neutral pH |
| Storage temperature | Minus 20 to minus 80 C | Long-term, lyophilized |
| Analytical method | RP-HPLC | Purity assessment |
| Typical purity | Greater than 95 percent | Research-grade material |
== Properties == 64Cu has a half-life of 12.70 hours and decays 61.5% of the time to 64Ni, of which 17.5% is positron emission and 44% by electron capture, and 38.5% by beta decay to 64Zn. The electron-capture branch emits a 1.346-MeV gamma ray in 0.472% of all decays, which could be used for tracing the isotope.
=== Biomedical === Nanoscale particles are used in biomedical applications as drug carriers or imaging contrast agents in microscopy. Anisotropic nanoparticles are a good candidate in biomolecular detection. Moreover, nanoparticles for nucleic acid delivery offer an unprecedented opportunity to overcome some drawbacks related to the delivery, owing to their tunability with diverse physico-chemical properties, they can readily be functionalized with any type of biomolecules/moieties for selective targeting. Using nanoparticles in cancer treatment is being extensively researched. Certain characteristics of the tumor microenvironment, including leaky vasculature and poor lymphatic drainage, lead to the accumulation of NPs in the tumor. This is known as the enhanced permeability and retention (EPR) effect, and is a type of passive targeting. Additionally, ligands that bind to certain expressed or over-expressed receptors in the tumor microenvironment can be conjugated to the surface of nanoparticles to actively target the tumor. The accumulation of nanoparticles in the tumor can reduce adverse side effects, which is a major drawback of chemotherapy. In drug delivery, the acidic pH of the tumor microenvironment is often exploited to increase the release of the drug from pH-sensitive materials. Additionally, some NPs can generate heat under laser irradiation (photothermal therapy) or alternating magnetic field (magnetic hyperthermia), which can both kill cancer cells, and release drugs loaded in the nanoparticle.
== IFITM3 == Interferon-induced transmembrane protein 3 (IFITM3) inhibits the replication of number of enveloped RNA viruses including influenza A, HIV and the Ebola and Dengue viruses. Consequently pharmacological induction of IFITM3 potentially could be used to treat a number of viral infections.
Sources: en.wikipedia.org
Basophils appear in many specific kinds of inflammatory reactions, particularly those that cause allergic symptoms. Basophils contain anticoagulant heparin, which prevents blood from clotting too quickly. They also contain the vasodilator histamine, which promotes blood flow to tissues. They can be found in unusually high numbers at sites of ectoparasite infection (e.g. ticks). Like eosinophils, basophils play a role in both parasitic infections and allergies. They are found in tissues where allergic reactions are occurring and probably contribute to the severity of these reactions. Basophils have protein receptors on their cell surface that bind IgE, an immunoglobulin involved in macroparasite defense and allergy. It is the bound IgE antibody that confers a selective response of these cells to environmental substances (e.g., pollen proteins or helminth antigens). Recent studies in mice suggest that basophils may also regulate the behavior of T cells and mediate the magnitude of the secondary immune response.
=== Mass-balance equations === In general, the calculations are rather complicated or complex. For instance, in the case of a dibasic acid, H2A dissolved in water the two reactants can be specified as the conjugate base, A2−, and the proton, H+. The following equations of mass-balance could apply equally well to a base such as 1,2-diaminoethane, in which case the base itself is designated as the reactant A:
=== Straight side chain === The genetic code has been described as a frozen accident and the reasons why there is only one standard amino acid with a straight chain, alanine, could simply be redundancy with valine, leucine and isoleucine. However, straight chained amino acids are reported to form much more stable alpha helices.
On the advice of his junior minister Lord Bellwin, a former leader of Leeds City Council, Heseltine ordered that nobody was to be hired without his personal approval. Heseltine instituted an internal audit system called "MINIS" ("management information system for ministers"), ironically, in Crick's view, as Heseltine's own company Haymarket had often been chaotically organised. Peter Hennessy likened it to "a Domesday Book". Heseltine personally interrogated the heads of department (many of whom felt he was interfering in internal civil service matters). The lengthy reports, showing organisation charts of each of the 66 directorates, expenditure, staff costs and forward plans, were made publicly available. Staff numbers were cut more deeply than in any other Whitehall department; one in twelve had gone within a year and nearly 30%, 15,000, by 1983; local government finance, under Terry Heiser, was the only department to receive extra resources. Thatcher was impressed by MINIS, and in February 1983 Heseltine was invited to give a presentation about them to other senior ministers and civil servants, in the hope that they might be adopted by other departments. There was little interest, but similar concepts were later adopted by Derek Rayner's Financial Management Initiative across Whitehall.
Sources: en.wikipedia.org
However, major drawbacks of SMB are the inability of separating a mixture into three fractions and the lack of solvent gradient applicability. In the case of antibodies, the state-of-the-art technique is based on batch affinity chromatography (with Protein A or Protein G as ligands) which is able to selectively bind antibody molecules. In general, affinity techniques have the advantage of purifying biomolecules with high yields and purities but the disadvantages are in general the high stationary phase cost, ligand leaching and reduced cleanability. The MCSGP process can result in purities and yields comparable to those of purification using Protein A. The second application example for the MCSGP prototype is the separation of three MAb variants using a preparative weak cation-exchange resin. Although the intermediately eluting MAb variant can only be obtained with 80% purity at recoveries close to zero in a batch chromatographic process, the MCSGP process can provide 90% purity at 93% yield. A numerical comparison of the MCSGP process with the batch chromatographic process, and a batch chromatographic process including ideal recycling, has been performed using an industrial polypeptide purification as the model system. It shows that the MCSGP process can increase the productivity by a factor of 10 and reduce the solvent requirement by 90%.
Produced by Frances Berrigan, directed by Christopher Swayne, made by Cicada Films with the Discovery Channel 8 September The Big G, about gravity; Saturn's gravity destroyed its moons, to make its rings; Newton's laws unleashed the industrial revolution; geophysicist Victoria Lagenheim of the USGS, and gravimetry (gravity mapping); physicist Gabriel Luther; astrophysicist Robert Kirshner of the Harvard-Smithsonian Center for Astrophysics; Andrulla Blanchette; Apollo asteroid (35396) 1997 XF11 will approach the Earth on 26 October 2028 at 600,000 miles; reproductive biologist Lynn Maxey Wiley of UC Davis; neurologist Edward Good; neuroscientist Muriel Ross of NASA Ames; astrobiologist James Clifford of NASA Ames; Ralph Pelligra, chief medical officer at NASA Ames; astronauts Bernard A. Harris Jr. and David Wolf (astronaut); the ISS would be complete by 2004; astrophysicist Alex Filippenko at University of California, Berkeley; astrophysicist Saul Perlmutter at Lawrence Berkeley National Laboratory; astrophysicist Adam Riess of the High-Z Supernova Search Team, who found in 1998 that the universe rate of expansion is increasing, winning the 2011 Nobel Prize for Physics.
== Efficacy and side effects == Counterintuitively to the drastic effect of thinly winged insect-venom on neurological processes, some toxins of these hymenopteran insects are used in the field of medicine. An example can be found in tertiapin-Q from the European honey bee (Apis mellifera) which is used in the treatment of pain, multiple sclerosis (MS), and rheumatoid arthritis. The spider wasp is also a hymenopteran insect but its pompilidotoxins are currently not linked to any existing drugs. Therefore there are also no indications for these compounds. PMTXs medical potential has been considered in the past but to no avail. Their possible characteristic to only enhance neuronal activity has already been nullified as early as in 1998 by Harsch et.al who experimentally found that α-PMTX could also disrupt the activity of rat cortical neurons irreversibly and immediately upon administration. The unpredictability of the toxin and the still rather large gap in information on the toxin, contribute to it not having been translated into medicine. However, even though pompilidotoxins are not used as drugs, they do hold a large medical value. This value comes forth from the fact that this neurotoxin of 13 amino acids is so much smaller than its fellow sodium channel-specific polypeptide toxins. For example, pompilidotoxins are much smaller than the conventionally studied sea anemone toxin that has 46 to 49 amino acids, or the α-scorpion toxin of even 60 to 65 residues.
Sources: en.wikipedia.org
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.
Repeated temperature cycling can promote aggregation and peptide degradation. Dividing material into single-use aliquots limits this risk.
Mass spectrometry is commonly used to confirm molecular mass and detect structural modifications. It is often paired with chromatographic purity assessment.
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.