The short version of C18 column fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-07-06 and is reviewed periodically as new material appears.
Human evidence remains limited to controlled studies. A phase 2 trial in adults with obesity reported large, dose-dependent reductions in body weight over 48 weeks, with gastrointestinal events as the most frequently recorded adverse effect. Phase 3 programs designated TRIUMPH, for obesity, and TRANSCEND, for type 2 diabetes, are intended to confirm efficacy and to characterize safety in larger populations. Related studies are examining conditions such as knee osteoarthritis in people with obesity and metabolic liver disease. Open questions include long-term tolerability, effects on lean mass, and what happens after treatment is stopped.
Retatrutide is an investigational synthetic peptide that acts on three receptor targets at once: glucose-dependent insulinotropic polypeptide, glucagon-like peptide-1, and glucagon. It is developed by Eli Lilly and appears in the literature and in trial registries under the code LY3437943. The molecule belongs to a class of engineered peptides designed to resist rapid breakdown and permit infrequent subcutaneous administration. No regulatory agency has approved it for clinical use, and all available human data come from controlled trials rather than from routine practice.
The intended pharmacology combines three signals in one molecule. GLP-1 receptor activation reduces appetite and slows gastric emptying, effects already exploited by approved incretin-based therapies. GIP receptor engagement is associated with improved insulin sensitivity and with direct effects on adipose tissue, although how much it contributes to overall outcomes is still debated. Glucagon receptor agonism raises energy expenditure and supports hepatic lipid handling, a mechanism that also tends to increase glucose output. The triple profile is hypothesized to produce a larger metabolic effect than single or dual agonism, but the relative weight of each receptor in humans is not settled.
Characterization panels may add amino acid analysis for compositional confirmation, circular dichroism for secondary structure in solution, and light scattering for aggregation tendency. Aggregation is a central concern for peptides bearing hydrophobic side chains, since it can lower measured potency and complicate accurate dosing. Stability studies examine temperature, humidity, pH, and light exposure over defined intervals, reporting the percentage of intact peptide remaining. Results depend strongly on the assay used, so comparing values across studies requires matching method details.
Peptide content and purity are commonly measured by reversed-phase high-performance liquid chromatography with ultraviolet detection, using gradient elution over a C18 column. Identity is confirmed by mass spectrometry, because the theoretical monoisotopic mass allows unambiguous assignment of the main component. Impurity profiling resolves deletion sequences, oxidized residues, and truncated fragments. Since the molecule carries a lipophilic side chain, mobile phases often include ion-pairing agents and organic modifiers to keep peaks symmetric.
| Property | Value | Notes |
|---|---|---|
| Compound class | Synthetic triple-agonist peptide | Single linear chain carrying three receptor activities |
| Reported molecular weight | Approximately 4731 Da | Calculated from the published sequence; sources vary slightly |
| Appearance | White to off-white lyophilized powder | Typical of purified research-grade peptides |
| Solubility | Freely soluble in water; poorly soluble in nonpolar solvents | Dissolves in aqueous buffer near neutral pH |
| Storage of dry powder | -20 °C or below, desiccated, protected from light | Avoid repeated temperature cycling |
Peptides in this class degrade mainly through hydrolysis, oxidation, and aggregation. The lipid modification improves plasma residence time but can also promote self-association in aqueous solution at higher concentrations. Oxidation of methionine and deamidation of asparagine residues are common chemical liabilities that accumulate during storage. Stability studies therefore track purity loss, aggregate formation, and changes in receptor-binding potency over time under defined temperature and humidity conditions.
Solid peptide is generally held as a lyophilised powder at low temperature to slow degradation, with desiccant to limit moisture uptake. Reconstituted solutions are less stable and are usually kept refrigerated and protected from light for short periods. Repeated freeze-thaw cycles are avoided because they encourage aggregation. Laboratory handling includes work in a fume hood or laminar flow cabinet to limit inhalation and contamination. Weighing and transfer steps are performed with antistatic tools to reduce static-driven loss of fine powder.
Characterising a peptide of this size relies on a combination of chromatographic and mass spectrometric techniques. Reversed-phase high-performance liquid chromatography separates the intact molecule from related impurities, while electrospray mass spectrometry confirms molecular mass and detects truncation or oxidation products. Peptide mapping after enzymatic digestion verifies the amino acid sequence and locates modified residues. Because the molecule carries a lipid chain, assays must also distinguish the correctly conjugated product from incompletely acylated species.
Research-grade peptide material is commonly supplied as a lyophilized powder, a form that limits degradation during transport and storage. Standard practice keeps such material cold and protected from light and moisture, with tighter conditions used for long-term archives. Once dissolved, solutions are generally considered less stable than the dry powder and are handled on shorter timescales. These established conventions derive largely from general peptide chemistry rather than from compound-specific evidence alone.
Identification and purity assessment typically rely on reversed-phase high-performance liquid chromatography, often paired with mass spectrometry. Mass measurement confirms the expected molecular mass and can reveal truncations or modifications. Peptide mapping and sequencing techniques provide sequence-level confirmation when needed. Because related peptide impurities can behave similarly in a single method, orthogonal techniques are usually combined. Reported purity values depend heavily on the method used and should be interpreted with that in mind.
== Familie == Benjamin „Ben“ List entstammt einer großbürgerlichen Frankfurter Familie. Er ist ein Urenkel des Nephrologen Franz Volhard und ein Ururenkel des Chemikers Jacob Volhard. Er ist ein Neffe der deutschen Nobelpreisträgerin Christiane Nüsslein-Volhard, die 1995 den Nobelpreis für Physiologie oder Medizin bekam. Sie ist die Schwester seiner Mutter. List ist verheiratet und hat zwei Söhne. Mit seiner Familie überlebte er den Tsunami vom 26. Dezember 2004 in Khao Lak in Thailand. List ist Fan der Fußballmannschaft von Eintracht Frankfurt.
== Leben == Das Studium der Chemie an der Freien Universität Berlin schloss List 1993 mit dem Diplom ab. Die Promotion erfolgte 1997 an der Johann Wolfgang Goethe-Universität Frankfurt am Main bei Johann Mulzer mit dem Thema Synthese eines Vitamin-B12-Semicorrins. Auf einen Postdoc-Aufenthalt am Scripps Research Institute in La Jolla, Vereinigte Staaten, mit Arbeiten über katalytische Antikörper folgte von 1999 bis 2003 seine Berufung als Assistant Professor am Scripps Research Institute in La Jolla im Department für molekulare Biologie. Im Jahr 2003 wurde er zunächst Arbeitsgruppenleiter am Max-Planck-Institut für Kohlenforschung, an dem er im Juli 2005 Direktor wurde.
Er gilt als einer der Begründer der asymmetrischen Organokatalyse, die ohne potentiell gesundheits- und umweltschädliche sowie teure Metallverbindungen auskommt. Im Gegensatz zur Enzymkatalyse werden dabei kleine organische Moleküle eingesetzt. Insbesondere entdeckte er die Möglichkeit, die Aminosäure Prolin, und damit eine natürlich vorkommende organische Substanz, als effizienten Katalysator für die Herstellung von optisch aktiven Produkten bei Reaktionen wie der Aldolreaktion einzusetzen. Er fand auch neue Methoden der textilorganischen Katalyse, bei der lösliche organische Katalysatoren an Textilien gebunden werden (zum Beispiel für die lokale Wasserversorgung in abgelegenen Gebieten), und der asymmetrischen Katalyse (speziell Asymmetric Counteranion-Directed Catalysis, ACDC). Asymmetrische Organokatalyse ist besonders wichtig bei bioaktiven organischen Verbindungen, bei denen die Chiralität der Moleküle entscheidend ist, etwa bei der Medikamentenherstellung. 2005 bis 2014 war er Sprecher des DFG-Schwerpunktprogramms 1179 Organokatalyse. Seit 2015 ist er Chefherausgeber von Synlett, bei der er schon 2011 Herausgeber war. Seit 2005 ist er außerdem einer der Herausgeber von Synfacts. Seit 2018 ist List einer von 15 Forschungsleitenden des Institute for Chemical Reaction Design and Discovery an der Hokkaido University in Sapporo, Japan.
== Ehrungen und Auszeichnungen == 2003 – Carl-Duisberg-Gedächtnispreis, Gesellschaft Deutscher Chemiker (GDCh) 2004 – Dozentenstipendium, Fonds der Chemischen Industrie seit 2004 – Honorarprofessor, Universität zu Köln (Institut für Organische Chemie) 2005 – Gastprofessor, Gakushūin-Universität, Tokio, Japan 2008 – Gastprofessor, Sungkyunkwan-Universität, Republik Korea 2012 – Otto-Bayer-Preis (dotiert mit 75.000 Euro) 2013 – Ruhrpreis für Kunst und Wissenschaft 2013 – Horst-Pracejus-Preis, Gesellschaft Deutscher Chemiker 2016 – Gottfried-Wilhelm-Leibniz-Preis 2018 – Mitglied der Deutschen Akademie der Naturforscher Leopoldina 2019 – Plenarvortrag beim Wissenschaftsforum Chemie der GDCh (Very Strong and Confined Chiral Acids: Universal Catalysts for Asymmetric Synthesis?) 2021 – Nobelpreis für Chemie für die Entwicklung der asymmetrischen Organokatalyse (gemeinsam mit David MacMillan) 2022 – Mitglied der 17. Bundesversammlung für Nordrhein-Westfalen (auf Vorschlag der CDU) 2022 – Mitglied der Nordrhein-Westfälische Akademie der Wissenschaften und der Künste 2022 – Mitglied der Akademie der Wissenschaften und der Literatur 2022 – Großes Bundesverdienstkreuz mit Stern der Bundesrepublik Deutschland, verliehen von Bundespräsident Frank-Walter Steinmeier 2023 – Ehrenbürger der Stadt Mülheim an der Ruhr 2024 – 16. Criegee-Vorlesung am Karlsruher Institut für Technologie
Sources: de.wikipedia.org
It is an investigational peptide that activates three hormone receptors: GIP, GLP-1 and glucagon. It is being studied mainly for obesity and type 2 diabetes, and it is not approved for any clinical use. Published information comes from controlled trials rather than from general practice.
No. As of the most recent public information it remains investigational in every jurisdiction. Material sold under this name outside trials is a research chemical, not an approved medicine. Current status should always be checked against regulator notices.
Dual agonists act on two receptors, usually GIP and GLP-1. Retatrutide adds glucagon receptor activity, which is associated with increased energy expenditure. Whether that third component adds clinically meaningful benefit over dual agonism remains an open question.
Reversed-phase liquid chromatography with ultraviolet detection is the standard approach, reported as area percent of the main peak. Orthogonal methods such as mass spectrometry confirm that the main peak has the expected mass. Purity figures are only comparable when column, gradient, and wavelength are matched.