Cagrilintide combines a modified amylin backbone with an acyl chain and a disulfide-stabilized ring, and confirming all three features are correctly present is the point of lot-level analytical testing.
Reversed-phase HPLC
HPLC separates the fully acylated, correctly cyclized peptide from incompletely conjugated or unmodified intermediates, with purity read per understanding HPLC purity. The acyl-chain conjugation in particular can produce a distinct impurity profile compared with unmodified peptides.
Mass spectrometry for identity
Mass spectrometry confirms the molecule's mass matches the fully modified sequence described in its chemistry article, distinguishing it from partially acylated byproducts or the unmodified peptide backbone — see HPLC vs. mass spectrometry.
Why this matters for a long-acting analog
Cagrilintide's research value as an extended-duration amylin-receptor agonist, detailed in its mechanism of action, depends specifically on the acyl-chain modification being intact; a lot with incomplete conjugation would behave more like a shorter-acting, less-engineered amylin analog and confound duration-focused comparisons, including against paired incretin compounds like semaglutide.
Documentation to expect
A lot-specific certificate of analysis with HPLC purity and mass-spec identity confirmation — see how to read a CoA.
Product page: Cagrilintide research vials.
Research Use Only. Supplied strictly for laboratory research and development — not for human or veterinary use, consumption, or any therapeutic or diagnostic purpose. This article is research education, not usage guidance.