A practical reference on 冻干粉: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-02-25. Anything still debated is marked as such rather than presented as settled.
Identity and purity are usually established with reversed-phase high-performance liquid chromatography for the main peak and with mass spectrometry for the observed molecular mass. Peptide mapping after enzymatic digestion confirms the primary sequence, while amino acid analysis provides a quantitative composition check. Size-exclusion chromatography and ion-exchange chromatography are used to look for aggregates and charge variants. Water content, residual solvents, and counter-ion content are measured separately, since a lyophilised powder is often reported on an as-is basis unless a correction is applied.
Research-grade material circulates through suppliers that differ widely in documentation and testing practice, so a certificate of analysis is a starting point rather than proof of quality. Independent verification typically repeats chromatographic purity and mass confirmation on the received lot, and compares results against a retained reference standard. Regulatory status varies by jurisdiction, and a substance cleared as a medicine is not interchangeable with a research chemical of the same name. Open questions include how closely non-pharmaceutical lots match approved material in impurity profile and in aggregate content.
Solid tirzepatide is handled as a lyophilised, hygroscopic peptide powder that should be kept desiccated, protected from light, and stored frozen, typically at or below minus twenty degrees Celsius for long-term retention. Material left at ambient temperature for extended periods can take up moisture, which promotes aggregation and deamidation. Commercial liquid presentations are kept refrigerated between two and eight degrees Celsius and are not frozen. Reconstituted laboratory solutions are generally held cold and used within a short window because hydrolysis and oxidation continue slowly in solution.
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。
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Lyophilised solid, may form a loose cake |
| Solubility class | Soluble in water | Practically insoluble in nonpolar solvents |
| Storage temperature, solid | -20 °C or below | Desiccated and protected from light |
| Storage temperature, liquid | 2-8 °C | Refrigerated, not frozen |
| Typical identity method | LC-MS | Observed mass compared with calculated mass |
Both receptors are class B G protein-coupled receptors that signal largely through Gs-mediated cyclic AMP production. Activation within pancreatic islets increases glucose-dependent insulin secretion and suppresses glucagon release when glucose is elevated. Outside the pancreas, signaling in the central nervous system and gut appears to influence appetite and gastric emptying. The relative contribution of each receptor to observed clinical effects remains under investigation, and the two pathways are not simply additive in practice.
Reported outcomes in large trials include dose-dependent weight reduction and improvements in glycemic markers over periods ranging from several months to more than a year. Whether the compound alters long-term cardiovascular or renal outcomes is being examined in dedicated outcome studies, so those questions remain open. Labeling describes gastrointestinal effects such as nausea and diarrhea, which tend to appear during dose escalation. Discontinuation rates and the durability of effects after treatment stops vary across study populations and are still debated.
Tirzepatide is a synthetic peptide developed as a dual agonist at the glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptors. Its structure is built on a GIP-derived backbone with non-natural amino acid substitutions and a fatty diacid side chain that promotes albumin binding and slows clearance. That modification supports once-weekly subcutaneous dosing. Registrational trial programs reported reductions in body weight and glycated hemoglobin alongside the drug's glycemic effects.
固体状态的 tirzepatide 通常以冻干粉形式保存，推荐在低温、避光、干燥条件下存放，常见区间为 2 至 8 摄氏度，长期保存可考虑更低温度并避免反复冻融。冻融循环会导致肽链聚集或析出，从而影响后续定量结果。容器密封性与湿度控制同样是稳定性研究中反复强调的因素。
溶解操作一般使用注射用水或适宜的水性缓冲液，必要时加入少量助溶剂以改善溶解速度，但应避免剧烈涡旋振荡，因为剪切力可能促进聚集。配制后的溶液在冷藏条件下的稳定时间通常短于固体形态，具体时限取决于浓度、缓冲体系与容器材质。是否加入防腐成分，则取决于用途是否为多次取样。
定量分析的主流方法是反相高效液相色谱联用紫外或质谱检测，利用肽在疏水固定相上的保留行为确定纯度与含量。对于生物基质中的浓度测定，常采用液相色谱串联质谱，并配合固相萃取或蛋白沉淀进行样品前处理。免疫分析法也可使用，但可能受到结构相关肽的交叉反应干扰。
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.
Identity and purity of tirzepatide are assessed mainly by reversed-phase high-performance liquid chromatography with ultraviolet detection, often paired with mass spectrometry. Because the molecule carries several modifications, gradient conditions are adjusted to resolve the intact peptide from deamidation and oxidation products. Enzymatic digestion followed by peptide mapping confirms the primary sequence and locates specific modifications. Quantitation in biological matrices typically uses liquid chromatography with tandem mass spectrometry after solid-phase extraction. Immunoassays are used less often, since antibody cross-reactivity with closely related peptides can bias results.
Tirzepatide is a synthetic peptide composed of 39 amino acids. It acts as a dual agonist at two incretin receptors, the glucose-dependent insulinotropic polypeptide receptor and the glucagon-like peptide-1 receptor. The molecule was designed by modifying the native sequence of glucose-dependent insulinotropic polypeptide to improve metabolic stability and extend its circulation time. Its structure includes several non-natural amino acid residues and a fatty acid side chain. These features distinguish it from earlier single-receptor incretin analogs studied in the same period.
The compound first appeared in the scientific literature as an investigational agent for type 2 diabetes. Clinical development proceeded through phase 1, phase 2, and phase 3 programs that measured glycemic control as a primary endpoint while recording body weight as a secondary outcome. Regulatory approval in the United States followed in 2022 for glycemic control, and a separate indication for chronic weight management was added later. Subsequent trials have examined cardiovascular outcomes in adults with elevated cardiovascular risk. Debates continue over how much of the observed effect derives from each receptor arm.
Structural work on the molecule centers on a C20 fatty diacid moiety attached through a linker to the peptide backbone. This side chain promotes reversible binding to serum albumin, which slows renal clearance and supports a prolonged action profile. The peptide backbone incorporates aminoisobutyric acid substitutions that limit recognition by digestive enzymes. Together these modifications produce a molecule that is stable enough for subcutaneous delivery but still dependent on careful manufacturing control. Analytical characterization of the active pharmaceutical ingredient typically follows the conventions used for other synthetic peptides.
Special care must be taken when supplementing the medium with FBS (fetal bovine serum), as it also contains small metabolites used for the biosynthesis of nucleosides. The use of dialyzed FBS is therefore advisable when defined labeling of all nucleosides is desired.
== Pharmacology == Vinblastine is a vinca alkaloid and a chemical analogue of vincristine. It binds tubulin, thereby inhibiting the assembly of microtubules. Vinblastine treatment causes M phase specific cell cycle arrest by disrupting microtubule assembly and proper formation of the mitotic spindle and the kinetochore, each of which are necessary for the separation of chromosomes during anaphase of mitosis. Toxicities include bone marrow suppression (which is dose-limiting), gastrointestinal toxicity, potent vesicant (blister-forming) activity, and extravasation injury (forms deep ulcers). Vinblastine paracrystals may be composed of tightly packed unpolymerized tubulin or microtubules. Vinblastine is reported to be an effective component of certain chemotherapy regimens, particularly when used with bleomycin and methotrexate in VBM chemotherapy for Stage IA or IIA Hodgkin lymphomas. The inclusion of vinblastine allows for lower doses of bleomycin and reduced overall toxicity with larger resting periods between chemotherapy cycles.
The mother of an 18-year-old who killed himself in 2021 sued anti-vaccine campaigner Gemma O'Doherty for misrepresenting and sensationalising his death in the freesheet, The Irish Light, last year to support conspiracy theory about the COVID-19 vaccine. 30 May – Ireland's 2022 census figures from the CSO show an older population, increased diversity, decreased religiosity, and a population surpassing five million for the first time since the great famine.
Sources: en.wikipedia.org
Islam dominates in Pakistan, with about 96.35% of the population being Muslim. Pakistan ranks second globally in Muslim population, and is home to 10.5% of the world's Muslims. Karachi is the largest Muslim city in the world. The majority follow Sunni Islam, with a significant presence of Sufism, while Shia Muslims constitute a minority. Shias represent between 5–25%. The Shia population in Pakistan was estimated at 42 million in 2019. As of 2012, 12% of Pakistani Muslims self-identify as non-denominational Muslims. The Ahmadis are a minority, officially considered non-Muslims. Ahmadis face persecution, banned from calling themselves Muslims since 1974.
In Australia, as of 2013 the drug was authorized for prescribing for severe cases of insomnia but was restricted as a Schedule 8 medicine. In France, as of 2016 flunitrazepam was not marketed. In Germany, as of 2016 flunitrazepam is an Anlage III Betäubungsmittel (controlled substance which is allowed to be marketed and prescribed by physicians under specific provisions) and is available on a special narcotic drug prescription as the Rohypnol 1 mg film-coated tablets and several generic preparations (November 2016). In Ireland, flunitrazepam is a Schedule 3 controlled substance with strict restrictions. In Japan, flunitrazepam is marketed by Japanese pharmaceutical company Chugai under the trade name Rohypnol and is indicated for the treatment of insomnia as well as used for preanesthetic medication. In Mexico, Rohypnol is legally available. In Norway, on January 1, 2003, flunitrazepam was moved up one level in the schedule of controlled drugs and, on August 1, 2004, the manufacturer Roche removed Rohypnol from the market there altogether. In South Africa, Rohypnol is classified as a Schedule 6 drug. It is available by prescription only, and restricted to 1 mg doses.
Because a commercial TOFMS uses a higher voltage pulsed extraction with longer flight tube with other optimized conditions, it generally has better sensitivity and resolution than a suitcase TOF. However, in the case of very high mass compounds, the suitcase TOF shows as good resolution and sensitivity as the commercial TOF. The suitcase TOF was also tested with a series of chemical weapons agents. Every compound tested was detected at levels comparable to standard analytical techniques for these agents.
== History == 2000: Four scientists from what was then the Agricultural University of Norway (NLH), now the Norwegian University of Life Sciences (UMB) had the idea of replacing traditional date-stamping with something that can give a more correct indication of remaining shelf life for temperature sensitive products, such as food and pharmaceuticals. 2001: The fundamental principles for a shelf-life indicator were verified in the laboratory. The company TimeTemp AS, now Keep-it Technologies, was founded in 2001 to develop the technology into a commercial product. 2003: TimeTemp comes in second place in DNB’s national innovation competition. 2003-2007: The technology is tested and developed in the university's laboratories, and a working laboratory prototype is created. Keep-it Technologies is granted a patent in a number of different countries, including the US, Canada, Australia and New Zealand. 2007-2009: With support from the Research Council of Norway, Keep-it Technologies initiates an R&D project to develop the technology from laboratory prototype to an industrial prototype, and test it on real products through a professional cold chain. 2010-2011: The company raises new investment capital and initiates an IFU project that develops the first consumer version of the indicator. The indicator is tested on the first products in the Norwegian grocery market. 2012: Keep-it indicator is commercialized in Norway with the Norwegian retailer, Rema 1000. 2018: Keep-it has indicators on 30 different fresh products at Rema 1000, Kolonial.no and Oslo University Hospital.
Sources: en.wikipedia.org
=== New books === Thomas Charles - Geiriadur Ysgrythyrol Richard Colt Hoare - Life of Giraldus Theophilus Jones - History of the County of Brecknock, vol. 1 Titus Lewis - A Welsh — English Dictionary, Geiriadur Cymraeg a Saesneg Robert Southey - Madoc
Gus Sackey (David Jonsson) is a new grad at Pierpoint, and one of the series' protagonists during the first two series. He is initially assigned to the Investment Banking Division (IBD) and transferred to the CPS desk after the death of his colleague Hari Dhar. Gus is openly gay and hails from an elite background, having graduated literae humaniores from both Eton College and the University of Oxford. Despite his upper-class upbringing, Gus is shown to be humble and morally principled, and feels undervalued within Pierpoint's cutthroat work culture. In series 1, Gus struggles to find a clear role after his team is dissolved and repeatedly alienates senior staff through his bluntness and frustration, including London office head Sara Dhadwal and his manager Clement Cowan. He also rekindles an affair with his former classmate Theo Tuck. On RIF day, Gus delivers a deliberately unserious presentation—beginning by reading from a note written as part of a bet—before walking out, and is not offered a permanent position. In series 2, Gus re-emerges working in politics after striking up a connection with MP Aurore Adekunle, who hires him as an aide. Gus feels fulfilled by the work—which largely involves speaking with everyday constituents about their struggles—despite his sister Sadie's objections. While working for Aurore, Gus begins a relationship with Leo Bloom, the son of hedge fund manager Jesse Bloom, and later leaks confidential government information about the approval of Amazon’s acquisition of pharmaceutical company FastAide to Harper.
Research and public pressure have led to bans on the use of Bisphenol A in bottles and cups to be used by children. In 2008 Walmart announced that it would stop selling baby bottles and food containers containing BPA. As of 2017, these were applied in at least 40 countries. Canada classified BPA as "toxic" in 2008 under the Canadian Environmental Protection Act. In 2011 use of bisphenol A in baby bottles was forbidden in all EU countries, in China, in Malaysia, and South Africa. In July 2012, the FDA stated that BPA would no longer used in baby bottles and sippy cups, in response to a petition from the American Chemistry Council stating that this was now in line with industry practice. Other countries such as Argentina and Brazil followed suit by prohibiting bisphenol A in baby bottles. Korea has extended its BPA ban to include all children's utensils, containers and packaging as of January 2020. There are calls for increased regulation of BPA in India.
Sources: en.wikipedia.org
It is normally kept frozen, desiccated, and away from light, with brief warming to room temperature before opening to limit condensation. Repeated freeze-thaw cycles are avoided because they stress the peptide. Once in solution, the material is held cold and used promptly.
Mass spectrometry gives the observed molecular mass, which is compared with the calculated value for the expected sequence. Reversed-phase chromatography shows retention behaviour and main peak purity. Peptide mapping adds sequence-level confirmation when the question requires it.
Typical entries include appearance, chromatographic purity as area percent, observed mass, water or residual solvent content, and the analytical methods used. The document reflects the lot tested and the laboratory that performed the work. It does not by itself establish that the delivered vial matches the tested lot.
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。