SemZama is Zama Biosciences’ designation for semaglutide, a synthetic 31-amino-acid analogue of glucagon-like peptide-1. Molecular formula C187H291N45O59, molecular weight 4113.58 g/mol.
Three modifications distinguish it from native GLP-1, and each solves a specific problem. An Aib residue at position 8 blocks DPP-4 cleavage, the enzyme that degrades native GLP-1 within minutes. Arginine replaces lysine at position 34 to direct the acylation site. And a C18 fatty diacid is conjugated at position 26, promoting albumin binding and extending plasma half-life sufficiently for weekly-interval protocols in study designs.
Native GLP-1 has a half-life of roughly two minutes. Semaglutide is a well-documented case study in how targeted modification converts a physiologically transient signalling peptide into a compound suitable for extended-interval research protocols.
Research context
Published work examines GLP-1 receptor agonism across glycaemic control, glucose-dependent insulin secretion, gastric emptying and appetite regulation via central pathways.
Semaglutide is the reference compound for single-receptor incretin agonism, which makes it the natural comparator for the broader agonists in this catalogue. TirZama adds GIP receptor activity; RetZama adds glucagon receptor activity on top of that. Studies isolating the contribution of each receptor typically use semaglutide as the single-agonist baseline.
For a fuller treatment of the sequence, published models and technical data, see the semaglutide research guide.
Specification
CAS number 910463-68-2. Supplied as a white lyophilized powder at 5mg, soluble in sterile or bacteriostatic water. This batch assayed at 99.12% purity, verified by HPLC and LC-MS at ILS Lab.
Handling
Reconstitute with bacteriostatic or sterile water, introducing the diluent against the vial wall and swirling gently rather than shaking. Store lyophilized at −20°C protected from light; refrigerate at 2–8°C once reconstituted.
Ships with a batch-specific Certificate of Analysis. Cross-check the batch ID printed on your vial against the CoA before use — see the guide to reading a CoA if you are unfamiliar with the format.
Frequently asked questions about semaglutide
What makes semaglutide different from native GLP-1?
Three targeted modifications. Native GLP-1 has a half-life of roughly two minutes because DPP-4 cleaves it almost immediately. An Aib residue at position 8 blocks that cleavage, Arg34 directs where acylation occurs, and a C18 fatty diacid at position 26 promotes albumin binding. The receptor-binding behaviour is retained; what changes is how long the molecule persists.
Semaglutide or tirzepatide for incretin research?
Semaglutide engages GLP-1 only; tirzepatide engages GLP-1 and GIP. For work isolating the contribution of GLP-1 signalling, semaglutide is the cleaner tool precisely because it is single-receptor — a dual agonist confounds attribution. Studies quantifying what GIP adds typically run both, using semaglutide as the baseline.
What purity should semaglutide be?
This batch assayed at 99.12% by HPLC with identity confirmed by LC-MS at ILS Lab. For an acylated peptide, mass spectrometry is the more informative of the two checks — it confirms the C18 diacid is present and correctly conjugated, which a purity percentage alone cannot establish.
How is semaglutide reconstituted and stored?
Bacteriostatic or sterile water. Introduce the diluent slowly against the inner wall of the vial and swirl gently — do not shake or vortex. Store lyophilized at −20°C protected from light; refrigerate at 2–8°C once reconstituted and avoid repeated freeze-thaw cycles.
Research use only. Not for human or veterinary use, not for use in diagnostic procedures, and not evaluated by the U.S. Food and Drug Administration.
