The short version of Purity assessment fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-06-11. Anything still debated is marked as such rather than presented as settled.
脂肪酸侧链的存在使该肽与血浆白蛋白结合能力增强,从而延长循环半衰期,支持每周一次给药的用药间隔。白蛋白结合同时改变组织分布特征,减慢肾脏清除速度。该设计思路在多种长效肽类药物中被反复采用,属于既定的药代动力学策略。
该化合物的名称与结构由国际非专利名称体系统一维持,不同文献中出现的同义写法主要在拼写顺序或盐形式描述上不同。研究者通常通过受体结合实验、细胞内环磷酸腺苷积累测定以及动物模型来确认其双激动活性。相当一部分分子层面的细节——例如两条受体通路之间的信号交叉作用——尚处于开放问题状态。
当前公开资料把 tirzepatide 归为肠促胰素类受体双重激动剂。它并非激素天然变体,而是经过序列改造的工程化肽。其分子量、等电点与疏水性等基础参数已在药典和化学数据库中收录,可作为分析检测和质量研究的参照。
Tirzepatide is a synthetic peptide of 39 amino acids that carries a C20 fatty diacid side chain attached through a linker. Its molecular formula is C225H348N48O68, and its molecular weight is about 4813 daltons. The compound belongs to the incretin mimetic class and is administered by subcutaneous injection. The fatty acid chain promotes binding to serum albumin, which slows renal clearance and extends the circulation time of the molecule. It was identified during screening of sequences derived from glucose-dependent insulinotropic polypeptide.
Tirzepatide activates both the glucose-dependent insulinotropic polypeptide receptor and the glucagon-like peptide-1 receptor, making it a dual agonist rather than a selective agent. Engagement of the GLP-1 receptor is linked to glucose-dependent insulin release, slower gastric emptying, and reduced appetite signalling. The relative contribution of the GIP arm remains an active research question; proposed roles include improved insulin sensitivity and altered adipose tissue handling. Receptor occupancy studies suggest the molecule interacts with both targets at circulating concentrations achieved during therapy.
| Property | Value | Notes |
|---|---|---|
| 分子类型 | 合成修饰肽 | 39 个氨基酸,含脂肪酸侧链 |
| 受体靶点 | GIP 与 GLP-1 受体 | 双重激动剂 |
| 分子量 | 约 4.8 kDa | 以游离肽计 |
| 外观 | 白色至类白色粉末 | 冻干形态常见 |
| 溶解性 | 可溶于水及水性缓冲液 | 溶解后宜低温保存 |
Purified material is typically handled as a lyophilized powder kept at or below minus twenty degrees Celsius, shielded from light and moisture. In that state the solid remains stable for extended periods, although repeated freeze-thaw cycling can encourage aggregation. Once dissolved, aqueous solutions are less durable and are generally held cold and used within a brief window. Buffer composition, pH and ionic strength all influence degradation rates, and mildly acidic to neutral conditions are commonly examined. Actual shelf life depends on formulation, concentration and container, so stability limits are established experimentally rather than assumed.
Verification of research-grade material involves checking purity, sequence and counter-ion content against a certificate of analysis. Reported purity figures usually reflect chromatographic area percentage and do not by themselves establish biological activity. Independent laboratories may repeat mass confirmation and peptide mapping to detect substitutions or truncations. Open questions concern how residual solvents, trace metals and subtle conformational variants affect measured behavior, and how consistently different suppliers define their specifications. Documentation of analytical methods matters as much as the headline purity number when results are compared across studies.
Routine characterization relies on reversed-phase high-performance liquid chromatography, often coupled to mass spectrometry, to confirm identity and estimate purity. Peptide mapping after enzymatic digestion verifies the amino acid sequence and locates appended groups such as the fatty acid chain. Size-exclusion chromatography detects aggregates and fragments, while ion-exchange chromatography resolves charge variants. Circular dichroism and nuclear magnetic resonance supply secondary and higher-order structural information in research settings. No single technique covers every attribute, so laboratories combine orthogonal methods and compare outcomes against a reference standard where one exists.
Long-term storage of lyophilised peptide powder is generally at minus twenty degrees Celsius or colder, with desiccant and protection from light. Short-term storage at two to eight degrees Celsius is common during active use. In solution, stability depends strongly on pH, concentration, and the presence of preservatives, and hydrolysis or aggregation can develop over weeks. Published stability data specific to this molecule are limited, so recommended conditions for research material are usually extrapolated from general peptide handling practice rather than from a dedicated study.
Bulk peptide material is normally characterised by reversed-phase high-performance liquid chromatography, which separates the target sequence from truncation products and other closely related impurities. Ultraviolet detection near 214 nanometres is common because the peptide backbone absorbs in that region. Mass spectrometry, usually electrospray ionisation coupled to a mass analyser, is used to confirm the molecular mass. Because the molecule carries a lipophilic side chain, gradient methods often need a relatively high organic modifier fraction to elute it within a practical retention window.
Like most synthetic peptides of this size, the material is commonly supplied as a lyophilised powder that appears white to off-white. It dissolves in aqueous buffers and in mixtures of water with a small proportion of organic solvent, though the fatty acid portion reduces solubility in pure water relative to short peptides. Hygroscopic behaviour is reported for many peptide powders, so weighing is usually performed quickly and under controlled humidity. Working solutions are typically prepared fresh and kept cold.
Development of tirzepatide took place under a research program that sought to test whether simultaneous engagement of two incretin receptors would produce greater metabolic effects than single-receptor agonism. Clinical trials were organized into the SURPASS series for type 2 diabetes and the SURMOUNT series for obesity and weight management. Regulatory clearance for type 2 diabetes came in 2022 in the United States, followed by approval for chronic weight management in 2023. The trial programs reported reductions in glycated hemoglobin and body weight relative to comparators, though long-term cardiovascular and durability data continue to accumulate.
The peptide backbone contains 39 amino acids and includes alpha-aminoisobutyric acid residues, which are not among the standard proteinogenic set. A C20 fatty diacid moiety is attached through a linker, allowing the compound to bind serum albumin and extend its circulation time. This albumin binding is the main reason the molecule supports once-weekly administration rather than more frequent dosing. The measured molecular mass is approximately 4,813 daltons, placing it firmly in the peptide rather than small-molecule class.
Tirzepatide is a synthetic linear peptide of 39 amino acids that acts as a dual agonist at the glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors. Its sequence derives from native GIP but incorporates non-natural residues and a C20 fatty diacid moiety linked to a lysine side chain. The lipophilic chain promotes albumin binding, which slows renal clearance and extends circulation time. The unmodified peptide has a molecular formula of C225H348N48O68 and a molecular mass near 4,813 daltons.
Receptor activation by tirzepatide raises intracellular cyclic AMP through Gs-coupled signalling at both targets. At the GLP-1 receptor the downstream effect includes glucose-dependent insulin release, suppressed glucagon secretion, delayed gastric emptying, and reduced appetite signalling in the hypothalamus. GIP receptor engagement adds insulinotropic activity and appears to influence lipid handling in adipose tissue. Because both receptors are stimulated at the same time, the pharmacological profile differs from that of selective GLP-1 receptor agonists, and the relative contribution of each arm remains an area of active investigation.
== Regulatory scrutiny == The Royal Australian College of General Practitioners (RACGP) raised concerns in 2023 about telehealth services using remote questionnaires to prescribe GLP-1 receptor agonists, questioning whether such methods provided adequate clinical assessment. The Therapeutic Goods Administration (TGA) warned telehealth companies against advertising prescription-only medicines directly to consumers. During GLP-1 medication shortages in 2023–2024, Eucalyptus partnered with compounding pharmacies to provide compounded semaglutide. This practice drew criticism from pharmaceutical manufacturers and regulators. The Australian federal government subsequently banned pharmacy compounding of GLP-1 drugs from October 2024. Media reports in The Sydney Morning Herald and The Australian questioned whether social media and influencer campaigns for Eucalyptus brands overstated treatment results. ABC's Media Watch raised concerns about whether television segments promoting the company's services blurred editorial and advertising boundaries. In response to regulatory concerns, Eucalyptus introduced phone-based GP consultations to replace asynchronous online forms. In June 2025, the TGA issued class-wide safety warnings for all GLP-1 and dual GIP/GLP-1 receptor agonists, including medications prescribed through Juniper, regarding aspiration risks during general anaesthesia. The warnings required updates to product information across all suppliers of these medications.
==== Supported on silica spheres – reduction of dyes ==== Silver nanoparticles have been synthesized on a support of inert silica spheres. The support plays virtually no role in the catalytic ability and serves as a method of preventing coalescence of the silver nanoparticles in colloidal solution. Thus, the silver nanoparticles were stabilized and it was possible to demonstrate the ability of them to serve as an electron relay for the reduction of dyes by sodium borohydride. Without the silver nanoparticle catalyst, virtually no reaction occurs between sodium borohydride and the various dyes: methylene blue, eosin, and rose bengal.
Despite the fact that the period of the wars of independence itself was marked by a rapid expansion of representative government, for several of the new nations the nineteenth century was marked by militarism because of the lack of well-defined political and national institutions. The armies and officers that came into existence during the process of independence wanted to ensure that they got their rewards once the struggle was over. Many of these armies did not fully disband once the wars were over and they proved to be one of the stabler institutions in the first decades of national existence. These armies and their leaders effectively influenced the course of political development. Out of this new tradition came the caudillos, strongmen who amassed formal and informal economic, military and political power in themselves.
Sources: en.wikipedia.org
Historic England. "Bawdsey Chain Home Station (1309533)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "Great Bromley Chain Home Station (1476819)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "Canewdon Chain Home Station (1412472)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "Dunkirk Chain Home Station (1377189)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "High Street Chain Home Station (1476863)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "Pevensey Chain Home Station (1476551)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "Rye Chain Home Station (1476520)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "Ventnor Chain Home Station (1306901)". Research records (formerly PastScape). Retrieved 9 October 2015. Early Radar Memories Archived 2 September 2010 at the Wayback Machine Memories of Sgt. Jean Semple, one of Britain's pioneer radar operators RAF Bawdsey Chain Home Radar Station at Subterranean Britain RAF Radar Museum RAF High Street picture Life at Darsham Deprecated link archived 19 April 2013 at archive.today – BBC Great Baddow Chain Home Mast & Radar Anniversary Chain Home Radar – A Personal Reminiscence, M Scanlan, GEC Review, 1993 Early radar development in the UK at purbeckradar.co.uk 60 (Signals) Group, Fighter Command Archived 16 November 2017 at the Wayback Machine (pdf)
=== English === Order, Sons of St. George - Organized after the Civil War by Englishmen in the anthracite coal-mining region of Pennsylvania to counter the Molly Maguires. The organization "took permanent shape" at Scranton in 1871. Membership was open to "Englishmen, their sons, and grandsons, wherever born". Beneficiary membership was limited to those between 18 and 50; those over 50 were allowed honorary membership. The Order required belief in a Supreme Being, reverence for the Holy Bible, and loyalty to one's adopted country. By 1896 the order had about 35,000 members in the United States, Canada, and Hawaii. Ritual based on the legend of St. George included a "language of words, signs and grips" that the member learned upon initiation which could identify him to other members of the order. The Orders emblem was St. George conquering the dragon. The system of sick benefits varied by the lodge and the inclination of members. There was also a funeral benefit for members and their wives and a benevolent fund for brethren and "any worthy Englishman in distress". Some lodges also provided physicians and medicine for sick members. There was also a female auxiliary, the Daughters of St. George, but it was not officially recognized by the Supreme Lodge. In 1923 the Order was accused of promoting pro-British propaganda in textbooks used in New York by a representative of Mayor John Francis Hylan. Sons of England Benevolent Society - Fraternal order for Canadians of English descent.
Many marine invertebrates feed on carrion including cephalopods (e.g. Octopus vulgaris), hermit crabs (e.g. Coenobita perlatus), squat lobsters (e.g. Munida tenuimana), star fish (e.g. Asterias rubens), sea anemones (e.g. Actinoscyphia aurelia), amphipods (e.g. Eurythenes gryllus), annelids (e.g. zombie worms), and ribbon worms (e.g. Parborlasia corrugatus). Types of carrion consumed include dead seals, pilchards, jellyfish and tunicates, bones from whale falls, and fishery discards such as whiting and langoustine. Marine necrophages are less useful in forensic science than terrestrial necrophages. This is partly because human deaths occur less frequently in marine settings than terrestrial settings, and partly because human remains are less likely to be recovered in marine settings. In addition, in any aquatic system, there are a large number of environmental and biological factors that can confound calculation of minimum post-mortem interval. These include current and wave action, water temperature, oxygen concentration, and a greater diversity of necrophagous organisms colonizing the remains.
It focused on seven vaccine-preventable severe illnesses, tuberculosis, polio, measles, smallpox, diphtheria, tetanus, pertussis, and made recommendations to governments and other organizations in terms of the vaccination schedule. The EPI has since expanded its scope to include older children, adolescents and adults. As of 2026, the WHO/EPI recommends universal vaccination against 12 vaccine diseases (and 2 more for high-risk groups).
Sources: en.wikipedia.org
The carbohydrate-insulin model (CIM) posits that obesity is caused by excess consumption of carbohydrate, which then disrupts normal insulin metabolism leading to weight gain and weight-related illnesses. It is contrasted with the mainstream energy balance model (EBM), which holds that obesity is caused by an excess in calorie consumption compared to calorie expenditure. According to the carbohydrate–insulin model, low-carbohydrate diets would be the most effective in causing long-term weight loss. Notable proponents of the carbohydrate–insulin model include Gary Taubes and David Ludwig. The CIM has been tested in mice and humans. Although some experts consider that these studies falsified the CIM, proponents disagree. Available evidence does not support the existence of a long-term advantage in weight loss for low-carbohydrate diets.
"It seems to me", Mellanby wrote to Florey, "that the line of work you are suggesting will be interesting and may prove to be of practical importance." Florey felt that far more would be required. On 1 November 1939, Henry M. "Dusty" Miller Jr from the Natural Sciences Division of the Rockefeller Foundation paid Florey a visit. Miller encouraged Florey to apply for funding from the foundation and supported his application. "The work proposed", Florey wrote in the application letter, "in addition to its theoretical importance, may have practical value for therapeutic purposes." His application was approved, with the foundation allocating US$5,000 (£1,250) per annum for five years. The Oxford team's first task was to obtain a sample of penicillin mould. This turned out to be easy. Georges Dreyer, Florey's predecessor, had obtained a sample of the mould in 1930 for his work on bacteriophages, viruses that infect bacteria. Dreyer had lost interest in penicillin when he discovered that it was not a bacteriophage, but he had continued to cultivate it. Dreyer had died in 1934, but Campbell-Renton had continued to culture the mould and was able to supply it to the Oxford team. The next task was to grow sufficient mould to extract enough penicillin for laboratory experiments. The mould was cultured on a surface of liquid Czapek-Dox medium. Over the course of a few days it formed a yellow gelatinous skin covered in green spores. Beneath this, the liquid became yellow and contained penicillin. The team determined that the maximum yield was achieved in ten to twenty days.
== Applications == Advanced Metering Infrastructure (AMI)/Advanced Meter Reading (AMR): provides two way meter communications, allowing commands to be sent toward the home for multiple purposes, including “time-of-use” pricing information, demand-response actions, or remote service disconnects. During periods of peak demand, utilities use these networks to throttle high-load devices in participating homes. Utilities may also institute time-of-use pricing schemes, where the home area network (HAN) is used to communicate the current price of energy to the consumer. Home Automation: allows household devices such as light switches and fixtures; thermostats and sensors; music, video and speaker systems; security controllers and appliances to network with one another to wirelessly automate the home. Hospitality: allows for wireless networking of the devices in the room without the need for a retrofit. The doors and the devices in the rooms can also be remotely monitored from a central location. Building Automation: provides building owners and property managers with HVAC, lighting, access and refrigeration control to monitor energy usage in real time to create more energy efficient environments. Asset Management: allows for remote monitoring and tracking of assets and cold chain. It also provides container security in shipping. Industrial Automation: wirelessly networks and automates industrial processes and allows for temperature, pressure and level sensing as well as providing temperature and flow control. Defense: provides both battlefield and shipboard monitoring.
Quantum chemical calculations of molecular and supermolecular systems, Ab initio Monte Carlo and MD simulations of liquids / solutions, Electrolyte solution structure, Ultrafast Dynamics of solutes, Molecular Modelling of biomolecules and drugs, QSAR / QSPR, Chemical Evolution of Peptides/ Proteins and Origin of Life
=== Lyra Health Inc. === In March 2020, Starbucks announced that starting from April 6, all U.S. employees and their eligible family members could use up to 20 free mental health therapy or coaching sessions per year. They could meet with a counselor face-to-face or video call and would also have unlimited access to self-care apps through Lyra Health Inc.
Sources: en.wikipedia.org
它属于合成修饰肽,同时激动 GIP 与 GLP-1 两种肠促胰素受体。这类分子通常被称为双重肠促胰素受体激动剂,与选择性 GLP-1 激动剂在靶点范围上不同。
分子上的脂肪酸侧链使其与血浆白蛋白结合增强,显著延长循环半衰期。半衰期延长后,稳定血药浓度可在较长的给药间隔内维持,因此常见用法为每周一次。
同时激活两条肠促胰素通路可能在胰岛素分泌、胃排空和食欲调节上产生叠加效应。与单靶点相比,临床研究中观察到的血糖与体重变化幅度通常更明显,但各通路的具体贡献比例尚无定论。
It is a synthetic 39-amino-acid peptide that acts on two incretin receptors, the GIP receptor and the GLP-1 receptor. It is given by subcutaneous injection and has a circulating half-life of roughly five days. It is not a small molecule and is not absorbed usefully from the gut in conventional oral form.