The short version of dual agonist fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-12-03 and is reviewed periodically as new material appears.
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.
In clinical research, tirzepatide has been studied in randomized controlled trials for glycemic control and body weight reduction. These trials typically measure changes in hemoglobin A1c and body weight over periods of several months. The drug is administered by subcutaneous injection, and its pharmacokinetic profile supports once-weekly dosing. Post-marketing surveillance continues to evaluate long-term outcomes and rare adverse events.
Tirzepatide is a synthetic peptide that acts as a dual agonist at the glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors. The molecule contains 39 amino acids and features a C20 fatty diacid moiety attached via a linker, which promotes albumin binding and extends its circulating half-life. Its sequence incorporates non-natural amino acids and modifications that reduce susceptibility to degradation by dipeptidyl peptidase-4. This dual receptor activity distinguishes it from selective GLP-1 receptor agonists.
| Property | Value | Notes |
|---|---|---|
| Typical analytical method | Reversed-phase HPLC with UV detection | Often paired with mass spectrometry for identity |
| Common synonyms | GIP/GLP-1 dual agonist; LY3298176 | Development codes appear in earlier literature |
| Purity specification | Usually 95% or higher by HPLC area | Research-grade lots are often 98% or higher |
| Solution storage | 2–8 °C, protected from light | Short term; avoid repeated freeze-thaw cycles |
| Dry powder storage | −20 °C or below, desiccated | Protected from moisture and light |
Long-term storage of the solid generally relies on temperatures at or below minus twenty degrees Celsius, while short-term working stocks may be held refrigerated. Light exposure is limited because photodegradation can alter side chains over extended periods. Solutions prepared for analysis are less stable than the dry powder and are typically used within the same working day. Buffer choice matters, since some aqueous conditions favor deamidation or oxidation at specific residues. Stability data are usually generated under defined accelerated conditions and then extrapolated with stated assumptions.
Identity and purity are established with reversed-phase high-performance liquid chromatography, often paired with mass spectrometry for confirmation of the expected mass. Peptide mapping after enzymatic digestion verifies the primary sequence and detects substitutions. Size-exclusion chromatography quantifies aggregates and fragments, which are the impurities most often tracked for peptides of this size. Residual solvents, counterions, and water content fall under separate tests described in pharmacopeial chapters. Circular dichroism or nuclear magnetic resonance may be used in research settings to probe secondary structure, though such methods are less common in routine release testing.
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.
Common degradation routes include hydrolysis of labile amide bonds, deamidation of asparagine and glutamine residues, oxidation of methionine and tryptophan, and non-covalent aggregation. Aggregates can form during freeze-thaw cycling, at elevated pH, or when peptide concentration is high. Each route produces characteristic chromatographic or mass shifts that are tracked during stability studies. Whether a given minor impurity alters biological activity is often an open question, and specification limits are typically set on identity and purity rather than on functional data for trace species.
Lyophilized material is generally held at -20 degrees Celsius or lower, desiccated and protected from light, where it remains stable for extended periods. Reconstituted or ready-to-use solution is usually kept at 2 to 8 degrees Celsius with minimal agitation. Repeated freeze-thaw cycles should be avoided because they promote aggregation and reduce the soluble monomer fraction. Shipment of frozen solid commonly uses dry ice, while refrigerated liquid moves with validated cold packs. Stability beyond documented periods is not established.
Characterization of the peptide relies on reversed-phase high-performance liquid chromatography for purity and related-substance profiling, with ultraviolet detection near 214 nanometers. Mass spectrometry confirms molecular mass and reveals modifications such as oxidation or deamidation. Peptide mapping after enzymatic digestion verifies the amino acid sequence, while amino acid analysis supplies compositional data. Circular dichroism and infrared spectroscopy are used to assess secondary structure, particularly the alpha-helical content that influences aggregation behavior in solution.
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.
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.
It has been shown that endoglin expression and TGF-beta secretion are attenuated in bone marrow stromal cells when they are cocultured with prostate cancer cells. Also, the downstream TGF-beta/bone morphogenic protein (BMP) signaling pathway, which includes Smad1 and Smad2/3, were attenuated along with Smad-dependent gene transcription. Another result in this study was that both Smad1/5/8-dependent inhibitor of DNA binding 1 expression and Smad2/3-dependent plasminogen activator inhibitor I had a reduction in expression and cell proliferation. Ultimately, the cocultured prostate cancer cells altered the TGF-beta signaling in the bone stromal cells, which suggests this modulation is a mechanism of prostate cancer metastases facilitating their growth and survival in the reactive bone stroma. This study emphasizes the importance of endoglin in TGF-beta signaling pathways in other cell types other than endothelial cells. TRC105 is an experimental antibody targeted at endoglin as an anti-angiogenesis treatment for soft-tissue sarcoma. Cluster of differentiation
Cannabis Analytical Science Program (CASP) is a forum where the science of hemp and cannabis analysis can be discussed and cannabis standards and methods developed. Analytical Solutions Forum (ASF) brings global stakeholders together to identify emerging needs and technologies in scientific analysis of food and related products. === Botanical Ingredients and Dietary Supplement Integrity Program === AOAC’s Botanical Ingredient and Dietary Supplement Integrity (BIDSI) Program focuses on coordinating all future consensus-driven need for development, validation, and implementation of methods for the analysis of a wide range of botanical ingredients and dietary supplements. === Stakeholder Program on Infant Formula and Adult Nutritionals === Stakeholder Program on Infant Formula and Adult Nutritionals program (SPIFAN) develops consensus-based standards and methods to make infant formula and adult nutritionals safer for babies and adults to consume.
The ligated mRNA-DNA-puromycin library is translated in Red Nova Lysate (Novagen) or E. coli S30 Extract System (Promega), resulting in peptides covalently linked in cis to the encoding mRNA. The in vitro translation can also be done in a PURE (protein synthesis using recombinant elements) system. PURE system is an E. coli cell-free translation system in which only essential translation components are present. Some components, such as amino acids and aminoacyl-tRNA synthases (AARSs) can be omitted from the system. Instead, chemically acylated tRNA can be added into the PURE system. It has been shown that some unnatural amino acids, such as N-methyl-amino acid accylated tRNA can be incorporated into peptides or mRNA-peptide fusions in a PURE system. After translation, the single-stranded mRNA portions of the fusions will be converted to heteroduplex of RNA/DNA by reverse transcriptase to eliminate any unwanted RNA secondary structures, and render the nucleic acid portion of the fusion more stable. This step is a standard reverse transcription reaction. For instance, it can be done by using Superscript II (GIBCO-BRL) following the manufacturer's protocol.
Recent data showed that Synacthen test results can be used to predict future recovery of HPA axis function in patients with reversible causes of Adrenal Insufficiency. == Other hormones and chemicals that will rise in the ACTH stimulation test == Progesterone – precursor to cortisol and aldosterone 17α-Hydroxyprogesterone – a progestogen steroid hormone related to progesterone Luteinizing hormone – a pituitary hormone that stimulates sex hormone production DHEA and DHEA-S – androgen hormones produced in the adrenal glands The test is also used to diagnose hypoadrenocorticism in dogs and sometimes cats. Dexamethasone suppression test Insulin tolerance test, another test used to identify sub-types of adrenal insufficiency Metyrapone, a drug used in the diagnosis of adrenal insufficiency Triple bolus test Renin, enzyme that converts angiotensinogen 1 to angiotensin 2, a precursor to aldosterone Renin–angiotensin–aldosterone system HPA axis, explains the connections of the hypothalamus, pituitary and adrenal glands Hypopituitarism Pituitary adenoma Adrenal adenoma Corticorelin
At the present time the Department promotes various scientific fields, running the whole gamut of base branches of classical physical chemistry: thermodynamics, kinetics, electrochemistry, catalysis, sorption processes. As the subjects of research, organic compounds unite all the aforesaid research areas. Over the last years staff members of the Department of Physical Chemistry made reports at conferences in many countries of the world: Canada, Poland, Republic of South Africa, Italy, Germany, Portugal, Czech Republic, USA, Ireland, Croatia, Spain, Sweden, Japan, Brazil. The head of the Department is Professor Boris N. Solomonov, Doctor of Science in Chemistry. The Department conducts research in the following fields:
Sources: en.wikipedia.org
The fragment molecular orbital method (FMO) was developed by Kazuo Kitaura and coworkers in 1999. FMO is deeply interconnected with the energy decomposition analysis (EDA) by Kazuo Kitaura and Keiji Morokuma, developed in 1976. The main use of FMO is to compute very large molecular systems by dividing them into fragments and performing ab initio or density functional quantum-mechanical calculations of fragments and their dimers, whereby the Coulomb field from the whole system is included. The latter feature allows fragment calculations without using caps. The mutually consistent field (MCF) method had introduced the idea of self-consistent fragment calculations in their embedding potential, which was later used with some modifications in various methods including FMO. There had been other methods related to FMO including the incremental correlation method by H. Stoll (1992). Later, other methods closely related to FMO were proposed including the kernel energy method of L. Huang and the electrostatically embedded many-body expansion by E. Dahlke, S. Hirata and later M. Kamiya suggested approaches also very closely related to FMO. Effective fragment molecular orbital (EFMO) method combines some features of the effective fragment potentials (EFP) and FMO. A detailed perspective on the fragment-based method development can be found in a review.
All mammalian alkaline phosphatase isoenzymes except placental (PALP and SEAP) are inhibited by homoarginine, and, in similar manner, all except the intestinal and placental ones are blocked by levamisole. Phosphate is another inhibitor which competitively inhibits alkaline phosphatase. Another known example of an alkaline phosphatase inhibitor is [(4-Nitrophenyl)methyl]phosphonic acid. In metal contaminated soil, alkaline phosphatase are inhibited by Cd (Cadmium). In addition, temperature enhances the inhibition of Cd on the enzyme activity, which is shown in the increasing values of Km. In humans, alkaline phosphatase is present in all tissues throughout the body, but is particularly concentrated in the liver, bile duct, kidney, bone, intestinal mucosa and placenta. In the serum, two types of alkaline phosphatase isozymes predominate: skeletal and liver. During childhood the majority of alkaline phosphatase are of skeletal origin. Humans and most other mammals contain the following alkaline phosphatase isozymes:
Outer membrane proteins are membrane proteins with key roles associated with bacterial cell structure and morphology; cell membrane homeostasis; the uptake of nutrients; protection of the cell from toxins including antibiotics; and virulence factors including adhesins, exotoxins, and biofilm formation. There are a number of outer membrane proteins that are specifically virulence-related. Outer membrane proteins consist of two major classes of protein - transmembrane proteins and lipoproteins. The transmembrane proteins form channels or pores in the membrane called porins, and actively pumping efflux channels. The outer membranes of a bacterium can contain a huge number of proteins. In E. Coli for example there are around 500,000 in the membrane. Bacterial outer membrane proteins typically have a unique beta barrel structure that spans the membrane. The beta barrels fold to expose a hydrophobic surface before their insertion into the outer membrane. Beta barrels vary in sequence and size that ranges from 8 to 36 beta strands. A subset of OMPs have a perisplasmic or an extracellular link to their beta barrel structure. An outer membrane protein is translocated across the inner membrane through Sec machinery, and finally inserted to the outer membrane by the barrel assembly machinery complex.
The Bergmann degradation is a series of chemical reactions designed to remove a single amino acid from the carboxylic acid (C-terminal) end of a peptide. First demonstrated by Max Bergmann in 1934, it is a rarely used method for sequencing peptides. The later developed Edman degradation is an improvement upon the Bergmann degradation, instead cleaving the N-terminal amino acid of peptides to produce a hydantoin containing the desired amino acid. The Bergmann degradation follows the earlier work of Bergmann and his close colleague Leonidas Zervas, combining the organic azide degradation of the Curtius rearrangement with the Bergmann-Zervas carbobenzoxy method, which they designed to occur under relatively mild conditions so as to allow peptide sequencing. A single round of the Bergmann degradation yields an aldehyde containing the sought after amino acid residue and the remaining fragment of the original peptide in amide form.
Sources: en.wikipedia.org
1,3-Beta-glucan synthase is a glucosyltransferase enzyme involved in the generation of beta-glucan in fungi. It serves as a pharmacological target for antifungal drugs such as caspofungin, anidulafungin, and micafungin, deemed 1,3-Beta-glucan synthase inhibitors. Under the CAZy classification system, fungi and plant members fall in the glycosyltransferase 48 family (GT48). Some members of the glycosyltransferase 2 family (Pfam PF13632), such as the curdlan synthase CrdS (Q9X2V0), also has a similar activity. The biosynthesis of disaccharides, oligosaccharides, and polysaccharides involves the action of hundreds of different glycosyltransferases. These enzymes catalyse the transfer of sugar moieties from activated donor molecules to specific acceptor molecules, forming glycosidic bonds. The family consists of various 1,3-beta-glucan synthase components including Gls1, Gls2, and Gls3 from yeast. 1,3-Beta-glucan synthase (EC 2.4.1.34.) also known as callose synthase catalyses the formation of a beta-1,3-glucan polymer that is a major component of the fungal cell wall. The reaction catalysed is:
After earning his doctorate in biochemistry, Lehninger held various faculty positions at the University of Wisconsin–Madison and the University of Chicago. In 1952, he went to the Johns Hopkins School of Medicine, assuming the title of DeLamar Professor of the Department of Biological Chemistry. He served in this position until 1978, when he was appointed to the role of University Professor of Medical Sciences. He held this title until his death in 1986. 1948 – Paul-Lewis Award in Enzyme Chemistry 1951 – Guggenheim Fellowship 1956 – Elected to the National Academy of Sciences 1959 – Elected to the American Academy of Arts and Sciences 1969 – Remsen Award of the American Chemical Society 1970 – American Philosophical Society 1986 – Passano Foundation Award Forthcoming in New Dictionary of Scientific Biography
AH receptor-interacting protein (AIP) also known as aryl hydrocarbon receptor-interacting protein, immunophilin homolog ARA9, or HBV X-associated protein 2 (XAP-2) is a protein that in humans is encoded by the AIP gene. The protein is a member of the FKBP family. AIP may play a positive role in aryl hydrocarbon receptor-mediated signalling possibly by influencing its receptivity for ligand and/or its nuclear targeting. AIP is the cellular negative regulator of the hepatitis B virus (HBV) X protein. Further, it's been known to suppress antiviral signaling and the induction of type I interferon by targeting IRF7, a key player in the antiviral signal pathways. AIP consists of an N-terminal FKBP52 like domain and a C-terminal TPR domain. AIP mutations may be the cause of a familial form of acromegaly, familial isolated pituitary adenoma (FIPA). Somatotropinomas (i.e. GH-producing pituitary adenomas), sometimes associated with prolactinomas, are present in most AIP mutated patients.
Sources: en.wikipedia.org
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.
Removing water slows hydrolysis and limits aggregation, so dry powder retains its quality attributes longer than a solution. Suppliers define a shelf life and retest date for the dried form at specified temperatures. Once dissolved, the practical working lifetime shortens considerably.
It generally lists appearance, identity by mass, purity by chromatography, water or residual solvent content, and the methods used. Storage recommendations and a retest date are commonly included. Values are reported against a supplier specification rather than a single universal standard.
It activates both GIP and GLP-1 receptors. This dual action differentiates it from selective GLP-1 agonists.