This is a working overview of Albumin binding, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-04-03 and is reviewed periodically as new material appears.
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 是一种由 39 个氨基酸组成的合成肽,分子结构上以 GIP 序列为骨架并引入脂肪酸侧链修饰,使其能够同时与葡萄糖依赖性促胰岛素多肽(GIP)受体和胰高血糖素样肽-1(GLP-1)受体结合。这种双重激动特性使它在同类肽类药物中区别于选择性 GLP-1 受体激动剂。该分子最早由一家制药公司在 2010 年代报道,随后进入糖尿病与体重管理领域的临床研究。
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.
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.
| 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 |
Development began in the 2010s, when researchers modified a GIP-based scaffold to add GLP-1 activity and then attached the fatty diacid to lengthen its half-life. Clinical evaluation proceeded through large phase 3 programmes in type 2 diabetes and in obesity, and regulators in the United States cleared the compound for type 2 diabetes in 2022 and for chronic weight management in 2023. Several cardiovascular and metabolic outcome studies are still reporting, so the picture of long-term benefit and risk is incomplete. Approvals in other regions followed on different timelines.
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.
After subcutaneous injection, absorption is gradual, and peak plasma levels are generally reached within one to three days. Albumin binding extends the apparent half-life to roughly five days, which supports a weekly administration schedule. Metabolism proceeds mainly through proteolytic cleavage of the peptide backbone and beta-oxidation of the fatty acid chain, rather than through cytochrome P450 pathways. Eliminated fragments are largely recycled through general protein turnover, and excretion of intact drug in urine is minimal. These properties distinguish the molecule from short-acting incretin mimetics.
Tirzepatide is a synthetic peptide of 39 amino acids engineered from the native glucose-dependent insulinotropic polypeptide sequence. Its structure incorporates several non-natural residues and a C-terminal segment derived from glucagon-like peptide-1, together with a C20 fatty diacid moiety attached through a linker. The lipophilic side chain promotes binding to serum albumin, which slows renal clearance after administration. The compound is classified as a dual incretin receptor agonist and is supplied as a lyophilized powder for reconstitution or as a preformulated solution, depending on the presentation.
The peptide activates two G protein-coupled receptors, GIPR and GLP-1R. Binding triggers adenylyl cyclase activity and raises intracellular cyclic AMP in pancreatic beta cells, which potentiates insulin release when glucose is elevated. Signaling in the central nervous system is associated with reduced appetite and lower energy intake, while effects on gastric emptying and glucagon secretion are also reported. Because activity at both receptors is retained, the pharmacological profile is often described as incretin-based rather than selective for a single receptor.
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.
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.
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.
Amino acid N-carboxyanhydrides, also called Leuchs' anhydrides, are a family of heterocyclic organic compounds derived from amino acids. They are white, moisture-reactive solids. They have been evaluated for applications the field of biomaterials. NCAs are typically prepared by phosgenation of amino acids: They were first synthesized by Hermann Leuchs by heating an N-ethoxycarbonyl or N-methoxycarbonyl amino acid chloride in a vacuum at 50-70 °C: A moisture-tolerant route to unprotected NCAs employs epoxides as scavengers of hydrogen chloride. This synthesis of NCAs is sometimes called the Leuchs method. The relatively high temperatures necessary for this cyclization results in the decomposition of several NCAs. Of several improvements, one notable procedure involves treating an unprotected amino acid with phosgene or its trimer. NCAs are prone to hydrolysis to the parent amino acid: RCHNHC(O)OC(O) + H2O → H2NCH(R)CO2H + CO2 Some derivatives however tolerate water briefly. NCAs convert to homopolypeptides ( [N(H)CH(R)CO)]n) through ring-opening polymerization:
After about four months, cerium-141, zirconium-95/niobium-95, and strontium-89 represent the largest share of radioactive material. After two to three years, cerium-144/praseodymium-144, ruthenium-106/rhodium-106, and promethium-147 are responsible for the bulk of the radioactivity. After a few years, the radiation is dominated by strontium-90 and caesium-137, whereas in the period between 10,000 and a million years it is technetium-99 that dominates.
== Adverse effects == In about 0.1% of cases people have had anaphylactic reactions to lixisenatide and in about 0.2% of cases the drug has caused pancreatitis. Use with insulin or sulfonylurea may cause hypoglycemia. In some cases, people with no kidney disease have had acute kidney injury and in some people with existing kidney disease the condition has gotten worse. Because lixisenatide is a peptide people can and do develop an immune response to it that will eventually make the drug ineffective; people who have developed antibodies to lixisenatide tend to have more inflammation at the injection site. At least 5% of people had nausea, vomiting, diarrhea, headache, or dizziness after taking lixisenatide.
== Transcripts == The gene GLS encodes three separate isoforms. Isoform 1 (or KGA) and isoform 3 (or Glutaminase C) are functional enzymes, while isoform 2 (or GAM) shows no enzyme activity. Isoform 1 is expressed in the brain and kidneys, while isoform 3 is mostly expressed in the brain, heart and pancreas. Neither isoform is expressed in the liver, distinguishing it from the glutaminase encoded by GLS2. Despite predictions that suggested that isoform 3 should undergo nonsense-mediated decay, it is highly expressed.
Flubber, also commonly known as slime, is a non-Newtonian fluid, easily made from polyvinyl acetate–based glues (such as white "school" glue) and borax. It flows under low stresses but breaks under higher stresses and pressures. This combination of fluid-like and solid-like properties makes it a Maxwell fluid. Its behaviour can also be described as being viscoplastic or gelatinous.
Sources: en.wikipedia.org
However, after the Qualifying Final between Collingwood and West Coast was drawn and replayed, Essendon lost to Collingwood in both the second semi-final and the grand final. Following the 1991 season, Essendon moved its home games from its traditional home ground at Windy Hill to the larger and newly renovated MCG. This move generated large increases in game attendances, memberships and revenue for the club. The club's training and administrative base remained at Windy Hill until 2013. Following the retirement of Tim Watson and Simon Madden in the early 1990s, the team was built on new players such as Gavin Wanganeen, Joe Misiti, Mark Mercuri, Michael Long, Dustin Fletcher (son of Ken) and James Hird, who was taken at No. 79 in the 1990 draft. This side became known as the "Baby Bombers", as the core of the 1993 premiership side was made up of young players early in their careers. The team won the 1993 Grand Final against Carlton and that same year, Gavin Wanganeen won the Brownlow Medal, the first awarded to an Essendon player since 1976. Three years later, James Hird was jointly awarded the medal with Michael Voss of Brisbane. In 2000, the club shifted the majority of its home games to the newly opened Docklands Stadium, signing a 25-year deal to play seven home matches per year at the venue, with the other four remaining at the MCG. The season was one of the most successful by any team in VFL/AFL history, and the club opened with 20 consecutive wins before they lost to the Western Bulldogs in round 21.
== Structure == AgRP is a paracrine signaling molecule made of 112 amino acids (the gene product of 132 amino acids is processed by removal of the N-terminal 20-residue signal peptide domain). It was independently identified by two teams in 1997 based on its sequence similarity with agouti signalling peptide (ASIP), a protein synthesized in the skin controlling coat colour. AgRP is approximately 25% identical to ASIP. The murine homologue of AgRP consists of 111 amino acids (precursor is 131 amino acids) and shares 81% amino acid identity with the human protein. Biochemical studies indicate AgRP to be very stable to thermal denaturation and acid degradation. Its secondary structure consists mainly of random coils and β-sheets that fold into an inhibitor cystine knot motif. AGRP maps to human chromosome 16q22 and Agrp to mouse chromosome 8D1-D2.
== Epidemiology == The condition affects adults more frequently than children and males more frequently than females. Most cases occur between the ages of 40 and 60. Polyarteritis nodosa is more common in people with hepatitis B infection.
Salts of imidazole where the imidazole ring is the cation are known as imidazolium salts (for example, imidazolium chloride or nitrate). These salts are formed from the protonation or substitution at nitrogen of imidazole. These salts have been used as ionic liquids and precursors to stable carbenes. Salts where a deprotonated imidazole is an anion are also well known; these salts are known as imidazolates (for example, sodium imidazolate, NaC3H3N2).
Elizabeth Tracy Mae "Bethe" Wettlaufer (née Parker; born June 10, 1967) is a convicted Canadian serial killer and former registered nurse who confessed to murdering eight senior citizens and attempting to murder six other people in southwestern Ontario between 2007 and 2016. With a total of 14 victims either killed or injured by her actions, she is described as one of the deadliest serial killers in Canadian history.
Sources: en.wikipedia.org
Fascia training describes sports activities and movement exercises that attempt to improve the functional properties of the muscular connective tissues in the human body, such as tendons, ligaments, joint capsules and muscular envelopes. Also called fascia, these tissues take part in a body-wide tensional force transmission network and are responsive to training stimulation. As of 2018 the body-wide continuity of this tensional system has been expressed in an educational manner within the Fascial Net Plastination Project. The FNPP brought together experts in anatomy, dissection, and plastination, and it was the first project of its kind to plastinate a complete human fascia specimen.
Although SJS can be caused by viral infections and malignancies, the main cause is medications. A leading cause appears to be the use of antibiotics, particularly sulfa drugs. Between 100 and 200 different drugs may be associated with SJS. No reliable test exists to establish a link between a particular drug and SJS for an individual case. Determining what drug is the cause is based on the time interval between first use of the drug and the beginning of the skin reaction. Drugs discontinued more than 1 month prior to onset of mucocutaneous physical findings are highly unlikely to cause SJS and TEN. SJS and TEN most often begin between 4 and 28 days after culprit drug administration. A published algorithm (ALDEN) to assess drug causality gives structured assistance in identifying the responsible medication. SJS may be caused by the medications rivaroxaban, vancomycin, allopurinol, valproate, levofloxacin, diclofenac, etravirine, isotretinoin, fluconazole, valdecoxib, sitagliptin, oseltamivir, penicillins, barbiturates, sulfonamides, phenytoin, azithromycin, oxcarbazepine, zonisamide, modafinil, lamotrigine, nevirapine, pyrimethamine, ibuprofen, ethosuximide, carbamazepine, bupropion, telaprevir, furosemide, and nystatin. Genetic susceptibility plays a significant role in drug-induced Stevens–Johnson syndrome. Individuals who carry HLA-B15:02 or HLA-A31:01 are at substantially increased risk of carbamazepine-induced Stevens–Johnson syndrome.
=== Nano and biological materials === FTIR is also used to investigate various nanomaterials and proteins in hydrophobic membrane environments. Studies show the ability of FTIR to directly determine the polarity at a given site along the backbone of a transmembrane protein. The bond features involved with various organic and inorganic nanomaterials and their quantitative analysis can be done with the help of FTIR.
=== Soviet use of RTGs === Many Beta-M RTGs produced by the Soviet Union to power lighthouses and beacons have become orphaned sources of radiation. Its design allowed for the use of normal industrial bolts instead of intrinsically safe or safety interlocked bolts (most likely to reduce cost), and did not require the use of intrinsically safe opening mechanisms or made any use of tamper resistant shielding systems. Several of these units have also been illegally dismantled for scrap metal, or been exposed to storm conditions, freezing and water penetration, common issues in those abandoned in the harsh Russian arctic. Some have even fallen into the ocean, or have defective shielding due to poor design or physical damage. The US Department of Defense cooperative threat reduction program has expressed concern that material from the Beta-M RTGs can be used by terrorists to construct a dirty bomb. However, the strontium titanate perovskite used is resistant to all likely forms of environmental degradation and cannot melt or dissolve in water. Bioaccumulation is unlikely as SrTiO3 passes through the digestive tract of humans or other animals unchanged, but the animal or human who ingested it would still receive a significant radiation dose to the sensitive intestinal lining during passage. Mechanical degradation of "pebbles" or larger objects into fine dust is more likely and could disperse the material over a wider area, however this would also reduce the risk of any single exposure event resulting in a high dose.
== Premise == The show's plot centers around the lives of half-sisters Mona and Dee Dee Thorne, who slowly become friends when they move into the same San Francisco apt building. Mona is the daughter of Phyllis Thorne, Charles Thorne's first wife, and Dee Dee is Charles' daughter from his second marriage to Deirdre "Big Dee Dee" Thorne. Initially, Mona resents Dee Dee because Dee Dee grew up in a wealthy and privileged household, while Mona and her mother struggled financially. As adults, Mona is more street-smart and cynical, but prone to impulsive decisions while Dee Dee is charming and optimistic, but naïve at times. Throughout the series, the sisters confront their past resentments and learn to lean on each other as they navigate their issues in work, love, and family.
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。
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.