GLP-1 5mg

What GLP-1 is

GLP-1 is our catalog name for a synthetic single-receptor agonist peptide, classified in in-vitro receptor pharmacology against the GLP-1 receptor, a member of the class B G-protein-coupled receptor family. The name is receptor nomenclature and nothing more: it records which receptor the molecule is characterized against, not any activity outside an assay. Structurally it is a 31-residue peptide with a free C-terminal acid, one non-coded α-aminoisobutyric acid (Aib) residue close to the N-terminus, and a single lysine whose side chain is acylated with a long C18 diacid through a short hydrophilic spacer.

That lipid modification is what separates it from an unmodified receptor ligand and dominates its chromatography. Within our receptor-named group it is the smallest molecule: GLP-1/GIP is roughly 700 Da heavier and GLP-1/GIP/Glucagon roughly 618 Da heavier, and each is a different sequence rather than a variant of this one. Our article on GLP-1, GIP and glucagon nomenclature explains how single, dual and triple designations are used.

GLP-1 5mg specification

How GLP-1 is analyzed

The acylated lysine makes this peptide far more hydrophobic than its length alone would suggest, so it retains strongly on reverse-phase media and elutes late in an acetonitrile gradient. Wide-pore stationary phases and a raised column temperature give noticeably sharper peaks than a standard small-pore C18 method. One tryptophan, one tyrosine and two phenylalanines give it real absorbance at 280 nm, although purity is integrated at around 214 nm, where every peptide-related species is visible. Electrospray spectra show a charge-state envelope rather than a single ion, with the triply and quadruply protonated forms expected near m/z 1372 and 1029.

Impurity classes worth watching are tryptophan oxidation (+16 Da), deamidation of the lone glutamine (+1 Da), truncated or deletion sequences from synthesis, and species with an incomplete or missing side-chain modification, which elute noticeably earlier. The reverse-phase HPLC purity for GLP-1 is published on this product page; vials carry no lot or batch identifiers and are matched to that published test by their crimp and cap color.

Research contexts for GLP-1

• Receptor-binding and cAMP reporter assays in recombinant cell lines expressing the cloned GLP-1 receptor
• Selectivity comparisons against the dual and triple receptor agonist peptides in the same catalog group
• Reverse-phase method development for lipidated peptides with late retention
• Mass spectrometric characterization of multiply charged, side-chain-modified peptides

This material is supplied solely as a reference compound for in-vitro and analytical laboratory work, and not for use in any person or animal.

GLP-1 questions

Why is the mass so high for a 31-residue peptide?

The side chain on the lysine, a C18 diacid joined through a spacer, adds several hundred daltons on top of the peptide backbone, bringing the total to about 4113.6 g/mol.

Is GLP-1 the same molecule as GLP-1/GIP?

No. The dual-receptor product is a longer, amidated sequence with a different formula and a mass near 4813.5 g/mol. The names share a prefix, not a structure.

Why does the chromatogram show a peak at 280 nm?

Tryptophan and tyrosine absorb in that region, so this peptide is visible at 280 nm, unlike short sequences with no aromatic residues. The 214 nm trace is still the one used for purity.