Tirzepatide
LY3298176 · GIP/GLP-1 dual agonist
Tirzepatide is a synthetic 39-residue peptide bearing a C20 fatty diacid moiety, studied as a dual GIP and GLP-1 receptor agonist in laboratory receptor-pharmacology models.
Analytical specification
| CAS number | 2023788-19-2 |
|---|---|
| Molecular formula | C225H348N48O68 |
| Average molecular weight | 4,813.45 g/mol |
| Amino-acid count | 39 |
| Peptide class | lipidated 39-residue peptide analogue |
| Physical form | Lyophilized powder |
| Research area | Metabolic research |
| Solubility | Soluble in sterile or bacteriostatic water; consult the lot COA for solvent guidance |
Reference values from public analytical chemistry. Confirm against the lot Certificate of Analysis before use in an assay.
Dual agonism as a design constraint
GIP and GLP-1 are related hormones acting at related receptors, with homologous but non-identical sequences. A single molecule engaging both must satisfy two sets of binding requirements simultaneously — a harder problem than single-receptor optimization, and part of why the molecule is longer than semaglutide. More residues means more positions available to reconcile competing constraints.
The stabilization strategy is the family standard: Aib substitutions to block dipeptidyl peptidase-4 cleavage, and a C20 fatty diacid through a linker for reversible albumin binding and extended circulation. The C20 chain is two carbons longer than semaglutide’s.
Consequences of size
At 39 residues, coupling efficiency compounds unfavourably: crude purity is lower and more purification is needed, which is reflected in cost per milligram. Deletion sequences shift mass by 1-3% and may barely move retention time, so LC-MS rather than UV-only chromatography is the appropriate release method.
The longer lipid makes it more hydrophobic than semaglutide — later retention, greater adsorption to labware, and a stronger tendency to aggregate in concentrated solution. Reconstitute gently, aliquot immediately, and prepare working dilutions fresh.
Available as
Documentation
Certificates of Analysis are published per lot on release. Look up a lot number to retrieve its certificate.