sourcing5 minupdated 2026-05-14
Questions to ask before trusting a source
A checklist you can screenshot: batch-linked COAs, third-party labs, sterility panels, cold-chain shipping, and refund policy.
Non-negotiables
A batch/lot-specific COA — not a generic 'representative' report.
Third-party lab (Janoshik, Freedom, ILS, Vanguard). In-house COAs are marketing, not evidence.
Both purity AND mass on the COA. Purity alone can be misleading if the mass is wrong.
Sterility panel for anything you plan to inject in research.
Nice-to-haves
Endotoxin (LAL) testing.
Cold-chain shipping option with ice packs for temperature-sensitive compounds.
Reship or refund policy if the package is delayed and warms up.
Public batch history you can cross-reference.
Research use only
This guide is educational reference material — not medical advice, not a prescription, and not an endorsement of self-administration.