In a Canadian research-peptide context, FOXO4-DRI sits within the longevity 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 FOXO4-DRI matters
FOXO4-DRI is a dominant-interfering retro-inverso peptide first characterized in Baar et al. (2017), where it was studied for selective induction of apoptosis in senescent cells in vitro. 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%. 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 FOXO4-DRI, the lifecycle is: receive the vial (dispatched within 2 business days, ~4 days in transit via Canada Post Xpresspost), 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. If your assay drifts, we run our retain against your in-hand material and pinpoint whether the variance is in the peptide or upstream in your reagent pipeline. This is the most-requested feature labs cite when asked why they reorder.
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/.