Semaglutide (GLP1-SM), catalogued at livvmore under the house code GLP1-SM, is a synthetic 31-residue peptide supplied strictly as a laboratory research reference material. This profile sets out its verified chemical identity, structural features, physical characteristics, and the analytical methods used to confirm identity and purity per batch. Every figure below is drawn from public chemistry registries so that a receiving laboratory can reconcile the reference material against an independent record before any bench work begins.
Compound identity and CAS registry
Semaglutide is assigned CAS registry number 910463-68-2 and is recorded in PubChem under compound identifier CID 56843331, with the corresponding DrugBank entry DB13928. It carries the Novo Nordisk development code NN9535 (also recorded as NNC 0113-0217, with the oral formulation designated OG217SC). In the chemistry literature it is categorised as a synthetic GLP-1 receptor-agonist peptide; this classification denotes the molecule’s mechanistic category in the literature and is not a statement of any outcome. livvmore handles the material only as an identity-defined reference standard, and the identifiers above let a laboratory match a received lot to the public registry record.
Molecular formula, weight, and structure
The molecular formula is C187H291N45O59, giving an average molecular weight of approximately 4113.6 g/mol (reported as 4113.64 g/mol in public registries). The molecule is a single 31-amino-acid chain based on the human GLP-1(7-37) backbone. Unlike some related analogues, the chain terminates in a free C-terminal carboxylic acid rather than a C-terminal amide. Its defining structural feature is a lipidation motif on the lysine side chain at backbone position 26: a C18 fatty diacid (octadecanedioic acid) conjugated through a gamma-glutamic acid residue and two AEEA (8-amino-3,6-dioxaoctanoic acid) spacer units. These substitutions account for the formula and mass given above.
Amino-acid sequence and modifications
Using GLP-1(7-37) residue numbering, the sequence is His7-Aib8-Glu9-Gly10-Thr11-Phe12-Thr13-Ser14-Asp15-Val16-Ser17-Ser18-Tyr19-Leu20-Glu21-Gly22-Gln23-Ala24-Ala25-Lys26-Glu27-Phe28-Ile29-Ala30-Trp31-Leu32-Val33-Arg34-Gly35-Arg36-Gly37. Relative to native GLP-1(7-37), the molecule carries two backbone substitutions and one side-chain conjugate: the non-canonical residue Aib (2-aminoisobutyric acid) replaces alanine at position 8, arginine replaces lysine at position 34, and the lysine at position 26 bears the lipid conjugate. In the peptide’s own 1-to-31 numbering these map to position 2 (Aib), position 28 (Arg), and position 20 (the lipidated lysine). The C18 fatty-diacid chain is attached to the epsilon-amino group of Lys26 by way of the gamma-glutamyl linker and the two AEEA spacers described above.
Appearance, solubility, and storage as reference material
The reference material is supplied as a lyophilised white to off-white powder and is reported as soluble in aqueous buffers. The lyophilised powder is kept cold and desiccated, protected from light and from repeated temperature change, and any aqueous solution is likewise held cold. As a modified peptide carrying a free C-terminal acid and an acidic lipid conjugate, it is stored and handled as a lipidated peptide reference standard. These notes describe storage and handling of the reference material at the bench only and are not use instructions.
Confirming identity and purity by LC-MS
Identity and purity are confirmed analytically rather than assumed. Reversed-phase HPLC (RP-HPLC) resolves the main peptide from process- and storage-related impurities and reports purity as a percentage of total peak area, while LC-MS and high-resolution mass spectrometry (HRMS) confirm identity by matching the measured mass of the intact peptide against the theoretical value calculated from the formula C187H291N45O59. livvmore materials are identity- and purity-tested at the USC Alfred E. Mann Multi-Omics Mass Spectrometry Core, a university laboratory, by LC-MS/HRMS on a per-batch basis, with the resulting Certificate of Analysis published for each lot. This per-lot record lets a receiving laboratory verify that the material in hand matches the registry identity before any bench work begins.
Related research peptides in the catalogue
Semaglutide sits alongside other GLP-family research peptides catalogued at livvmore. Related reference materials include Retatrutide (GLP3-RT) and Tirzepatide (GLP2-TZ). The full GLP research peptide collection groups these compounds together, and the identity comparison sets out their formulae, weights, and structural differences side by side for reconciliation against the registry record.
For laboratory research use only. Not for human or veterinary use.
Frequently asked questions
What is the CAS number of Semaglutide?
Semaglutide is assigned CAS registry number 910463-68-2. It is also recorded in PubChem under CID 56843331 and in DrugBank as DB13928, and carries the development code NN9535 (also NNC 0113-0217).
What is the molecular formula and molecular weight of Semaglutide?
The molecular formula is C187H291N45O59, corresponding to an average molecular weight of approximately 4113.6 g/mol (reported as 4113.64 g/mol in public registries).
How many amino acids does Semaglutide contain?
Semaglutide is a single chain of 31 amino acids based on the human GLP-1(7-37) backbone, with an Aib residue at position 8, an arginine substitution at position 34, and a C18 fatty-diacid conjugate on the lysine side chain at position 26.
How is the identity and purity of Semaglutide verified?
Purity is measured by RP-HPLC as a percentage of total peak area, and identity is confirmed by LC-MS/HRMS against the theoretical mass of the formula C187H291N45O59. livvmore tests each batch at the USC Alfred E. Mann Multi-Omics Mass Spectrometry Core and publishes a Certificate of Analysis for every lot.
How should lyophilised Semaglutide reference material be stored at the bench?
The lyophilised powder is kept cold and desiccated, protected from light and from repeated temperature change, and any aqueous solution is likewise held cold. These notes describe storage and handling of the reference material only and are not use instructions.