Tirzepatide — wholesale 10-vial kits

Research context

Tirzepatide was designed on a GIP-like backbone and modified so that it also activates the GLP-1 receptor. The two Aib substitutions protect it from cleavage by dipeptidyl peptidase-4, and the fatty-diacid side chain on lysine 20 binds serum albumin, which is why it behaves as a long-acting molecule in experimental systems.

Origin and molecular design. Tirzepatide was discovered at Eli Lilly under the code LY3298176, and its in-vitro characterization, mouse pharmacology and first clinical pharmacology were reported together in Molecular Metabolism in 2018. The FDA GSRS record describes a 39-residue, C-terminally amidated peptide with Aib at positions 2 and 13 and a C20 fatty diacid attached to Lys20 through a γ-glutamic acid–2×AEEA (OEG) linker. Its C-terminal GPSSGAPPPS segment is the tail of exendin-4. Lilly's later triple agonist retatrutide uses a closely related architecture to add glucagon-receptor activity.

In the laboratory it is a standard tool for incretin research. Published pharmacology (Willard et al., JCI Insight, 2020) describes it as an imbalanced and biased agonist: receptor-occupancy analysis showed greater engagement of the GIP receptor than the GLP-1 receptor, it mimics native GIP at the GIP receptor, and at the GLP-1 receptor it favors cAMP generation over β-arrestin recruitment while driving weaker receptor internalization than GLP-1. In primary islet experiments in the same study, β-arrestin-1 limited the insulin response to GLP-1 but not to GIP or tirzepatide. That profile makes it a common comparator in receptor-binding, signaling-bias and receptor-trafficking studies, and in rodent metabolic models run alongside selective GLP-1 receptor agonists such as semaglutide.

U.S. regulatory status: tirzepatide is the active ingredient of FDA-approved drug products marketed by Eli Lilly: Mounjaro (NDA 215866, first approved May 2022) and Zepbound (NDA 217806, first approved November 2023). The tirzepatide sold by WholesalePeptide.us is a research reference compound, not a drug product, supplied only for in-vitro, analytical and preclinical laboratory research.

Analytical laboratories also use tirzepatide to develop and qualify LC-MS and RP-HPLC methods for acylated peptides, where the counter-ion, water content and net peptide content reported on a COA all affect how much material is actually in a vial. The sequence has also been used as a scaffold for imaging probes: a fluorine-18-labelled NOTA conjugate of a tirzepatide analog was reported in 2026 as a PET tracer for simultaneous GLP-1 and GIP receptor targeting, work that depends on well-characterized starting peptide.

When ordering tirzepatide for comparator work, check that the COA mass matches the full acylated molecule rather than the unacylated backbone; incomplete acylation is the impurity that matters most for this class. Groups comparing incretin agonists usually run tirzepatide alongside semaglutide and retatrutide, and mixed kits count toward one wholesale tier.

Research areas

• Dual GIP / GLP-1 receptor agonism
• Signaling bias at the GLP-1 receptor (cAMP vs β-arrestin)
• GLP-1 receptor internalization and trafficking assays
• Albumin binding and half-life extension of acylated peptides
• Comparator arms in rodent metabolic models
• Peptide scaffolds for receptor-targeted imaging probes
• RP-HPLC and LC-MS method qualification

U.S. regulatory status of the compound (as an active ingredient): FDA-approved active ingredient (Mounjaro, Zepbound). Supplied here as a research reference material, not the drug product. The material sold here is a research reference chemical, not a drug product.

Handling and storage

• Store lyophilized vials at −20 °C, sealed, protected from light and moisture.
• Let the vial reach room temperature before opening to limit condensation on the powder.
• Use low-binding plastics for dilute solutions; acylated peptides adsorb to untreated surfaces.
• Aliquot reconstituted material and freeze once; avoid repeated freeze–thaw.