GLP-1 Research Peptides Explained: Semaglutide, Tirzepatide and Retatrutide

The GLP-1 class is one of the most actively studied groups of peptides in metabolic science. This overview explains, at a molecular level, what distinguishes semaglutide, tirzepatide and retatrutide as research compounds. It is provided for educational purposes only; all three are supplied strictly for laboratory research.

What “GLP-1” refers to

GLP-1 stands for glucagon-like peptide-1, an incretin involved in glucose and energy-balance signaling. Research peptides in this class act as receptor agonists — molecules engineered to bind and activate one or more incretin receptors. The differences between the compounds come down to which receptors they target and how they are structured for stability.

Single, dual and triple agonists

• Semaglutide is a single GLP-1 receptor agonist, widely used as a reference compound in metabolic research models.
• Tirzepatide is a dual agonist that targets both the GLP-1 and GIP (glucose-dependent insulinotropic polypeptide) receptors.
• Retatrutide is a triple agonist studied for activity at the GLP-1, GIP and glucagon receptors.

Because they engage different receptor combinations, these peptides are valuable tools for researchers investigating incretin signaling in vitro and in model systems.

Why structure matters in research

Small structural modifications — such as fatty-acid chains that extend a peptide’s half-life — are part of what differentiates these molecules. For research to be meaningful, the material must match its stated sequence and purity, which is why mass-spectrometry confirmation and a batch COA are essential.

Sourcing research-grade GLP-1 peptides

GetAll Peptides supplies this class verified to greater than 99% purity for laboratory research. Explore single vials for method development or 10-vial bundles for larger studies.