In a Canadian research-peptide context, SS-31 sits within the longevity class of reference standards. This post collects what HPLC-verified labs need to source, store, and reproducibly use this material, drawn from public literature and Pure North's reference-standard handling practices.
Why SS-31 matters
SS-31 is a mitochondria-targeted tetrapeptide that concentrates in the inner mitochondrial membrane, where it associates with cardiolipin — a property that has made it a focus of mitochondrial-disease research models. In a reference-standard context, 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 for the standards it does stock is 99.0%, with the catalog average at 99.18%, and every shipped lot carries a Janoshik-Analytical-verified COA archived publicly at /lab-results/.
The protocol short-version
For Canadian research labs working with SS-31, the lifecycle is: on receiving the lyophilized vial, transfer it 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
For the standards it stocks, Pure North holds a 5-year retain sample on every lot. If an assay drifts, the retain can be run against in-hand material to pinpoint whether the variance is in the peptide or upstream in the reagent pipeline. This is the most-requested feature labs cite when asked why they reorder.
Where to source it in Canada
SS-31 is not currently stocked in the Pure North Peptides catalog. For the reference standards Pure North does carry, the company is Canadian-based and ships across Canada via Canada Post Xpresspost — orders are dispatched within 2 business days, with typical transit around 4 days. Browse the available catalog at /products/. Read more on storage and handling in our storage guide, on dispatch and transit in our shipping policy, lot verification at /coa-verify/, or the public lot archive at /lab-results/.