Metabolic research

Canada GLP-1 research-peptide class comparison: Sema, Tirz, Reta, Cagri

Published 2025-12-21 · Pure North Peptides Editorial · Canada

A side-by-side data sheet of the four most-ordered metabolic peptides at Pure North, with HPLC purity and lot history references.

In a Canadian research-peptide context, GLP-1 sits within the metabolic class of reference standards. This post collects what HPLC-verified labs need to source, store, and reproducibly use this material, sourced from public literature and Pure North's published lot history.

Why GLP-1 matters

The GLP-1 class draws heavy interest in metabolic research, and reproducibility hinges on purity. The reproducibility gap on most catalogs comes from one place: lots that don't hit ≥ 99% HPLC purity get sold at lower price points instead of being rejected. Pure North's published purity floor is 99.0%, with the average across the catalog at 99.18%. Of this class, the one currently stocked at Pure North is Retatrutide 20 mg. Every lot we ship has a Janoshik-Analytical-verified COA archived publicly at /lab-results/ from synthesis onwards.

The protocol short-version

For Canadian research labs working with GLP-1 class reference standards, the lifecycle is: receive the vial (Canada Post Xpresspost transit averages ~4 days from dispatch), transfer immediately to a research-grade −20 °C freezer, reconstitute in sterile bacteriostatic water at the working concentration your protocol specifies, and use within the storage window noted on the lot's COA. Avoid repeated freeze-thaw cycles — every cycle introduces measurable assay drift even on lots that meet the purity floor.

Cross-batch reproducibility

Pure North holds a 5-year retain sample on every lot. The retained material gives the lab a fixed reference point if you need to investigate downstream assay drift against the original release lot.

Where to source it in Canada

Pure North Peptides is Canadian-based and ships across Canada via Canada Post Xpresspost — orders are dispatched within 2 business days, with typical transit around 4 days. Free shipping over $250 CAD; flat $25 below that. Browse the catalog at /products/. Read more on storage and handling in our storage guide, our shipping policy, lot verification at /coa-verify/, or the public lot archive at /lab-results/.

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