dual agonist comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2025-11-03. Where a claim depends on a specific study, the study is described rather than over-claimed.
As a peptide, tirzepatide is handled as a lyophilised solid in research settings and as a preserved solution in finished products. Aqueous solubility is pH dependent and reaches a minimum near the isoelectric point, which lies close to pH 5.4. Stock solutions are typically prepared in neutral or slightly basic buffer to limit precipitation. The solid is hygroscopic and should be equilibrated to room temperature before opening so that condensation does not form on the powder surface.
Recommended storage for reference material is a freezer at approximately -20 degrees Celsius, protected from light and moisture. Commercial injectable presentations are stored refrigerated between 2 and 8 degrees Celsius and must not be frozen. Product labelling generally permits a limited period at controlled room temperature once dispensed, with the exact window depending on the presentation. Repeated temperature cycling is avoided because it can promote aggregation or deamidation of the peptide chain.
Identity and purity are assessed by reversed-phase high-performance liquid chromatography, with mass confirmation by electrospray ionisation mass spectrometry. Peptide mapping after enzymatic digestion verifies the primary sequence. Size-exclusion chromatography quantifies aggregates, while circular dichroism provides a secondary-structure fingerprint. Bioanalytical quantification in plasma uses immunoassay or LC-MS/MS. Reported purity for research-grade lots is commonly 95 percent or higher, and residual water content is checked by Karl Fischer titration.
The peptide shares degradation routes common to modified peptides: deamidation of asparagine and glutamine residues, oxidation of methionine, and backbone hydrolysis under extreme pH. Lyophilized material is generally more stable than a solution, and residual water content directly affects the rate of hydrolysis. In liquid form, aggregation and visible particles can appear after agitation or repeated freeze-thaw cycles. Stability studies therefore track monomer content, aggregate content, and potency over months under defined temperature and humidity.
Cold-chain handling is standard for formulated product, with dry powder stored frozen and ready-to-use solutions refrigerated. Light exposure is minimized because photodegradation of certain amino acid side chains is possible. Shipping and temperature-excursion studies are used to establish whether short deviations affect quality attributes. Documentation supplied with research material usually includes a certificate of analysis listing purity, identity confirmation, and water or residual solvent content. Users are expected to confirm that material meets the stated specification before use.
| Property | Value | Notes |
|---|---|---|
| Appearance | white to off-white powder | Lyophilised solid form |
| Solubility | pH dependent; low near pI | Minimum close to pH 5.4 |
| Storage temperature | -20 C solid; 2-8 C solution | Protect from light |
| Isoelectric point | approx. pH 5.4 | Controls solubility minimum |
| Common analytical method | RP-HPLC with mass detection | Purity and identity checks |
Published work supports the view that engaging two incretin receptors produces changes in glucose handling and body weight larger than those seen with single-receptor activation. Why that difference arises is not fully settled. Open questions include how much of the observed weight effect depends on central versus peripheral signaling, and whether the two receptors form interacting complexes. Most reported findings come from controlled trials and animal models, and translation between species is imperfect. Further research is expected to refine these points over time.
Tirzepatide is a synthetic peptide built from 39 amino acid residues. Its sequence is related to human glucose-dependent insulinotropic polypeptide, with modifications that include a C-terminal extension and a C20 fatty diacid joined through a linker. Those changes raise the molecule's affinity for serum albumin, which slows renal filtration and lengthens the time it stays in circulation. The free base has an average molecular mass near 4813.5 daltons. The compound is made by solid-phase peptide synthesis followed by chromatographic purification.
At the receptor level, tirzepatide activates both the glucose-dependent insulinotropic polypeptide receptor and the glucagon-like peptide-1 receptor. Both belong to the class B family of G protein-coupled receptors and signal largely through cyclic AMP accumulation. The compound binds the two receptors with differing affinity, and the pattern of signaling at each site is described in the literature as biased rather than simply proportional to occupancy. Tissues carrying these receptors include pancreatic islets, adipose tissue, the central nervous system, and the gastrointestinal tract. The relative weight of each receptor population in producing metabolic effects continues to be studied.
An extended fatty diacid moiety promotes binding to serum albumin, which slows renal clearance and extends the circulating half-life to roughly five days. That property supports once-weekly administration and largely explains the dosing interval described in clinical reports. Published data come mainly from large randomised programmes that evaluated glycaemic control and body weight over periods of many months. Long-term outcomes beyond those trial windows, including what happens after treatment stops, remain an active area of investigation.
Tirzepatide is a synthetic peptide built from thirty-nine amino acids. Its sequence is derived from native glucose-dependent insulinotropic polypeptide, or GIP, with several non-natural residues and a fatty diacid side chain attached through a linker. The molecule behaves as a dual agonist at two incretin receptors, GIP and GLP-1, instead of targeting a single receptor. This dual engagement separates it from earlier single-receptor incretin compounds and underpins most of its reported pharmacological activity.
Dual agonism at the GIP and GLP-1 receptors underlies the observed pharmacology. Activation of GLP-1 receptors raises glucose-dependent insulin release, lowers glucagon secretion, slows gastric emptying and reduces appetite. GIP receptor activation contributes additional effects on adipose tissue and on energy balance, and the combined action on appetite appears larger than either pathway alone in animal models. Signalling bias and the relative contribution of each receptor arm to weight-related effects remain areas of active investigation.
Structure-activity work shows that fatty acid length, linker chemistry and the position of acylation all influence albumin affinity and receptor potency. Plasma protein binding exceeds 99 percent, which restricts distribution and slows renal clearance. Degradation proceeds largely through general proteolysis and fatty acid oxidation rather than cytochrome P450 metabolism, so exposure to common oxidative drug interactions is limited. Whether these clearance routes vary meaningfully between individuals is not fully established.
The molecule is a synthetic 39-amino-acid peptide whose backbone derives from the sequence of human glucose-dependent insulinotropic polypeptide, with several substitutions that raise metabolic stability and shift receptor preference. A C20 fatty diacid is attached through a short linker to a lysine side chain, a modification that increases binding to serum albumin. The reported monoisotopic mass is approximately 4813 Da. Near neutral pH the peptide carries a net negative charge, and the lipid tail makes the molecule markedly more hydrophobic than the unmodified parent sequence.
Chikungunya vaccines are vaccines intended to provide acquired immunity against the chikungunya virus. As of 2025, two vaccines have been licensed in some countries. These are Ixchiq, a live attenuated vaccine from Valneva, and Vimkunya manufactured by Bavarian Nordic which utilises virus-like particle technology. The most commonly reported side effects of Ixchiq include tenderness at the injection site, as well as headache, fatigue, muscle pain, joint pain, fever, and nausea. However the license for Ixchiq has been suspended or restricted in some countries due to the risk of severe side effects, particularly in older people.
== History == Justus von Liebig showed in 1829 that hippuric acid differed from benzoic acid and he named it, and in 1834 he determined its constitution, while in 1853 French chemist Victor Dessaignes (1800–1885) synthesized it by the action of benzoyl chloride on the zinc salt of glycine. It was also formed by heating benzoic anhydride with glycine, and by heating benzamide with monochloroacetic acid.
== Contributions to yachting == In retirement John Knox pursued his lifelong interest in yachting, applying scientific rigour to the field of anchoring. He invented the Anchorwatch, a strain gauge which measures the force on an anchor chain, in order to alert crew when their anchor is at risk of slipping during a stormy night. Knox used the Anchorwatch device to establish a testing procedure for measuring an anchor's holding force, and conducted years of experiments on Scotland's beaches to measure the efficiency of most anchor designs available on the global market. His work on anchor testing culminated in the design of his own optimised Knox Anchor, now commercially manufactured in the UK.
=== Club song === The club's theme song, "See the Bombers Fly Up", is thought to have been written c. 1959 by Kevin Andrews in the home of player Jeff Gamble at which time Kevin Andrews was living. The song is based on the tune of Johnny Hamp 's 1929 song "(Keep Your) Sunny Side Up" at an increased tempo. Jeff Gamble came up with the line 'See the bombers fly up, up' while Kevin Andrews contributed all or most of the rest. At the time, "(Keep Your) Sunny Side Up" was the theme song for the popular Melbourne-based TV show on Channel 7 Sunnyside Up. The official version of the song was recorded in 1972 by the Fable Singers and is still used. The song, as with all other AFL clubs, is played prior to every match and at the conclusion of matches when the team is victorious.
Sources: en.wikipedia.org
van Krevelen, D.W. (1950). "Graphical-statistical method for the study of structure and reaction processes of coal", Fuel, 29, 269–84. van Krevelen, D.W. and Schuyer, J. (1957) Coal science. Elsevier publishing company. The chemistry and technology of petroleum
=== Fuels === Another use of cryogenics is cryogenic fuels for rockets with liquid hydrogen as the most widely used example, with liquid methane starting to become more prevalent in recent years. Liquid oxygen (LOX) is even more widely used but as an oxidizer, not a fuel. NASA's workhorse Space Shuttle used cryogenic hydrogen/oxygen propellant as its primary means of getting into orbit. LOX is also widely used with RP-1 kerosene, a non-cryogenic hydrocarbon, such as in the rockets built for the Soviet space program by Sergei Korolev. Russian aircraft manufacturer Tupolev developed a version of its popular design Tu-154 with a cryogenic fuel system, known as the Tu-155. The plane uses a fuel referred to as liquefied natural gas or LNG, and made its first flight in 1989.
One interview in 2015 with the then Director of the White House Office of National Drug Control Policy under the Obama administration, Michael Botticelli, where he states that because opioid users are predominantly 'white and middle class', they "know how to call a legislator, [and] fight with their insurance company." In October 2017, Marino withdrew his nomination after it was reported that his relationship with the drug industry might be a conflict of interest. In July 2017, FDA commissioner Scott Gottlieb stated that for the first time, pharmacists, nurses, and physicians would have training made available on appropriate prescribing of opioid medicines, because opioid addiction had become the "FDA's biggest crisis". Trump nominated his then deputy chief-of-staff, James Carroll as the acting director of the Office of National Drug Control Policy in 2018. In January 2019, Carroll was approved by the Senate. In April 2017, the Department of Health and Human Services announced their "Opioid Strategy" consisting of five aims:
Healing the Wounds (HTW) is a British charity launched in December 2009 to help provide support and care for British servicemen and women suffering from post-traumatic stress disorder It was founded by Kevin Richards, a former British Army combat medic, who recognised the lack of aftercare support and treatment for sufferers of PTSD in Wales.
the producer phase of a military supply extends from determination of procurement schedules to acceptance of finished supplies by the military services the consumer phase of a military supply extends from receipt of finished supplies by the military services, through issue for use or consumption. A supply chain is a set of linked activities associated with providing material from a raw material stage to an end user as a finished good. Supply control is the process by which an item of supply is controlled within the supply system, including requisitioning, receipt, storage, stock control, shipment, disposition, identification, and accounting. A supply point is a location where supplies, services and materials are located and issued. As a single moving entity, a supply point location is temporary and mobile, normally being occupied for up to 72 hours. Sub-suppliers are those suppliers who provide materials to other suppliers within the supply chain. In other supply chain management contexts they are referred to by tier, second-tier suppliers serving first-tier suppliers, etc. The European Union refers to sub-suppliers in its objective to improve cross-border market access in the defence sector.
Sources: en.wikipedia.org
In Japan in 675, the Emperor Tenmu prohibited the killing and the eating of meat during the busy farming period between April and September but excluded the eating of wild birds and wild animals. These bans and several others that followed over the centuries were overturned in the nineteenth century during the Meiji Restoration. In China, during the Song dynasty, Buddhist cuisine became popular enough that vegetarian restaurants appeared where chefs used ingredients such as beans, gluten, root vegetables and mushrooms to create meat analogues including pork, fowl, eggs and crab roe and many meat substitutes used even today such as tofu, seitan and konjac originate in Chinese Buddhist cuisine.
=== Former markets === Russia – Pizza Hut began operating in Russia in 1991, when food supplies dwindled during the 1991 Soviet coup d'état attempt, prompting Russian president Boris Yeltsin to call Pizza Hut deliveries. Pizza Hut suspended operations in response to the 2022 Russian invasion of Ukraine. Later some restaurants re-opened operations under rebranded new trademark PittsaN (ПиццаН). Panama – In 2022, the Pizza Hut chain ceased its operations in Panamanian lands after reporting economic losses. Argentina – Pizza Hut opened in Argentina in 1983; however, they withdrew some time later. They returned in the mid-1990s but withdrew again in 1998 due to poor sales success. It was announced that it will be brought back to the country in 2025, but the exact date has not been confirmed. Chile – In 2025, the Pizza Hut chain downsized its operations in Chile as one of its two franchising concerns, Food Delivery Brands (which also handled Telepizza), went bankrupt as a result of the economic crisis the country had faced in the past decade and increasing competition from rival chains such as Little Caesars and Papa John's.
== Publications == J. Kopeček, J. Yang, "Polymer Nanomedicines". Advanced Drug Delivery Reviews 156, 40–66 (2020) L. Li, Y. Li, C.-H. Yang, D.C. Radford, J. Wang, M. Janát-Amsbury, J. Kopeček, J. Yang, "Inhibition of Immunosuppresive Tumors by Polymer-Assisted Inductions of Immunogenic Cell Death and Multivalent PD-L1 Crosslinking". Advanced Functional Materials 30:1908961 (2020) L. Li, J. Wang, Y. Li, D.C. Radford, J. Yang, J. Kopeček, "Broadening and Enhancing Functions of Antibodies by Self-Assembling Multimerization at Cell Surface". ACS Nano 13, 11422–11432 (2019) J. Yang, L. Li, J. Kopeček, "Biorecognition: A Key to Drug-free Macromolecular Therapeutics". Biomaterials 190–191, 11–23 (2019) J. Wang, L. Li, J. Yang, P.M. Clair, M. Glenn, D.M. Stephens, D.C. Radford, K.M. Kosak, M.W. Deininger, P.J. Shami, J. Kopeček, "Drug-free Macromolecular Therapeutics Induce Apoptosis in Cells Isolated from Patients with B Cell Malignancies with Enhanced Apoptosis Induction by Pretreatment with Gemcitabine". Nanomedicine: Nanotechnology, Biology and Medicine 16, 217–225 (2019). J. Yang, R. Zhang, H. Pan, Y. Li, Y. Fang, L. Zhang, J. Kopeček, "Backbone Degradable HPMA Copolymer Conjugates with Gemcitabine and Paclitaxel: Impact of Molecular Weight on Activity toward Human Ovarian Carcinoma Xenografts". Molecular Pharmaceutics 14, 1384–1394 (2017) J.M. Hartley, T.-W. Chu, E.M. Peterson, R. Zhang, J. Yang, J. Harris, J.
== Career == Harrington was a programmer at the video game developer Dynamix and a designer on the Windows NT operating system at Microsoft. In 1996, he founded Valve with Gabe Newell, another former Microsoft employee. Harrington sold his Microsoft shares to fund his half of the startup. His wife at the time, Monica Harrington, was Valve's marketing strategist in its early years. Harrington worked as a programmer on Valve's first game, Half-Life (1998), and funded its development with Newell. It was a critical and commercial success. Harrington said: "At Microsoft you always wonder, 'Is it me being successful or is it Microsoft?' But with Half-Life I knew Gabe and I had built that product and company from scratch." On January 15, 2000, Harrington sold his stake in Valve to Newell and left to spend time with his wife. According to Newell, Harrington did not want to risk another project after the success of Half-Life. In 2006, Harrington co-founded the photo editing service Picnik with his friend and former colleague Darrin Massena. Picnik was acquired by Google in March 2010. Harrington left Google in March 2011. In January 2012, he co-founded another company with Massena, Catnip Labs. Harrington was CTO at the Committee for Children from 2016 to 2018, and CTO of Amplion from November 2018 until March 2020.
Zopiclone, sold under the brand name Imovane among others, is a benzodiazepine-like drug (Z-drug) used as a pharmaceutical treatment for insomnia. While molecularly distinct from benzodiazepine drugs, zopiclone's mechanism of action is similar: it increases the transmission of the neurotransmitter gamma-aminobutyric acid (GABA) in the central nervous system, via positive allosteric modulation at GABAA neurons. Zopiclone is considered a sedative and CNS depressant. Zopiclone and other benzodiazepine-like drugs like zaleplon and zolpidem are addictive. Within days to weeks, the body can become accustomed to the effects of zopiclone. The risk of developing tolerance with benzodiazepine-like drugs is comparable to benzodiazepines. When the dose is then reduced or the drug is abruptly stopped, withdrawal symptoms similar to those of benzodiazepine withdrawal may result. Benzodiazepine-like drugs decrease sleep latency by 10 to 20 minutes. However, no benzodiazepine-like drug has shown clinically significant increase in total sleep time. Zopiclone is recommended only to be taken at the lowest effective dose, with a duration of 2–3 weeks, for short-term insomnia. Use of zopiclone more than 4 weeks is not recommended. It is dangerous to take with benzodiazepines, sedatives, alcohol or other drugs affecting the central nervous system. In the United States, zopiclone is not commercially available, although its active stereoisomer, eszopiclone, is.
Sources: en.wikipedia.org
Solid material is normally kept frozen at about -20 degrees Celsius, desiccated and protected from light. Solutions are held cold and used within a defined window because degradation products accumulate over time.
Mass spectrometry, usually electrospray ionisation coupled to liquid chromatography, gives an observed mass for comparison with the theoretical value. Peptide mapping after digestion provides complementary sequence-level confirmation.
Short exposure during weighing and handling is generally tolerated, but prolonged storage above refrigerated conditions raises the risk of deamidation, oxidation, and aggregation. The rate depends on pH, buffer composition, and concentration.
Reversed-phase liquid chromatography with ultraviolet detection is the usual approach, frequently combined with mass spectrometry for identity. Purity is reported as the area percentage of the main peak. Related impurities eluting near the main peak are usually summed and reported separately.