Pure North Peptides Journal · Compendium
Tirzepatide reference standard: a research overview for Canadian labs
Published 2024-01-28 · Pure North Peptides Editorial · Canada
Short answer. Tirzepatide is a 39-amino-acid synthetic dual agonist of the GLP-1 and GIP receptors, supplied lyophilized as a research reference standard. Pure North does not currently stock Tirzepatide — within this class the GLP-1-class reference standard Pure North currently stocks is Retatrutide 20 mg (a GLP-1/GIP/glucagon tri-agonist), supplied for in-vitro research use. Email purenorthpeptides@proton.me to ask about future availability.
Sequence and structure
Tirzepatide carries a γGlu-C20 fatty-diacid side chain at Lys20 that drives albumin binding. The dual GLP-1R/GIPR engagement profile distinguishes it pharmacologically from semaglutide (a GLP-1R mono-agonist) and retatrutide (a GLP-1R/GIPR/glucagon-receptor tri-agonist) in receptor-pharmacology terms.
Reference standard quality criteria
- HPLC purity ≥ 99% by reverse-phase analysis at 220 nm, lot-specific.
- ESI-MS confirmation at the theoretical mass of 4813.45 Da ± 0.5 Da.
- Net peptide content ≥ 80% by amino acid analysis (AAA), excluding counter-ion mass.
- Residual TFA < 1.0% from cleavage chemistry.
- LAL endotoxin < 0.5 EU/mg for cell-based assay compatibility.
Common research applications
Comparative cAMP and β-arrestin recruitment screens against semaglutide, in-vitro receptor-binding affinity (typical Ki low-nanomolar at GLP-1R and GIPR), and downstream signaling phenotypes in HEK293 cells stably transfected with the relevant receptors. Cross-batch HPLC fingerprint comparison is the simplest reproducibility check; we publish the lot-specific COA on every release at /lab-results/.
Reconstitution and storage
Allow the lyophilized vial to equilibrate at room temperature for 20 minutes before opening. Reconstitute with 1.0–2.5 mL of sterile bacteriostatic water, swirling gently — do not vortex. Solubility is excellent at neutral pH; the cake should clear within 60 seconds. Reconstituted solution is stable 28 days at 2–8 °C; for longer storage, aliquot to low-binding tubes and hold at −80 °C with a single freeze-thaw maximum.
Why source domestically
US bulk imports of GLP-1 class peptides see CBSA examination rates above 20% according to publicly reported customs data, with seizure outcomes for shipments missing import documentation. Domestic Canadian sourcing eliminates that variable entirely. See our customs guide for the full picture.
Tirzepatide is not currently in the Pure North Peptides catalog. Email purenorthpeptides@proton.me if you would like to be notified if it is added in the future, or browse the current catalog →
Frequently asked questions
What is Tirzepatide's molecular weight?
Theoretical mass 4813.45 Da; ESI-MS confirmation should fall within 0.5 Da of that value on a competent COA.
How does Tirzepatide differ from semaglutide?
Tirzepatide is a dual GLP-1R/GIPR agonist; semaglutide is a GLP-1R mono-agonist. The added GIPR engagement produces a distinct downstream signaling profile.
Where can I buy Tirzepatide reference standard in Canada?
Tirzepatide is not currently stocked in the Pure North Peptides catalog. The GLP-1-class reference standard Pure North currently stocks is Retatrutide 20 mg, supplied for in-vitro research. Email purenorthpeptides@proton.me to ask about future availability, or browse the current catalog.
How is Tirzepatide stored?
Lyophilized, desiccated, sealed under nitrogen. After reconstitution, 2–8 °C for 28 days or −80 °C aliquots for longer.
Is Tirzepatide approved as a drug?
It is supplied strictly as a laboratory reference standard for research use only. Health Canada has not approved it for therapeutic use.
Disclaimer: All Pure North Peptides products are supplied for laboratory research use only. They are not approved by Health Canada as drugs. See our research-use declaration for full terms.