Built for the researcher who reads the fine print.
Purity Peptides started with a simple frustration: research-grade peptides shouldn't require a leap of faith. If the lab you're buying from can't tell you the exact HPLC method, the endotoxin level, and the storage window in plain English — they shouldn't be shipping compounds.
What every vial must clear.
Independent third-party HPLC
Every lot is analyzed by an outside ISO-17025 lab — never by the manufacturer we source from. If a batch tests below 99% purity, it doesn't leave the freezer.
COA on every vial
The certificate of analysis you download is lot-matched to the vial number on your sticker. Methods, endotoxin panel, and bioburden testing are printed on it, not summarized.
Cold-chain shipping
Peptides ship in insulated boxes with medical-grade ice packs, standard on every order. Free at $200+, and we monitor transit time to avoid Friday-to-Monday dwell.
Reconstitution guidance included
Every product page has a step-by-step protocol written by researchers, not marketers — including exact BAC-water volumes and syringe-unit math.
Storage protocols documented
Lyophilized shelf life, post-reconstitution refrigerated stability, and multi-use vial handling are all documented per compound. No guessing.
Transparent pricing
We audit six vendors every Monday. Our published prices already beat them, so you never need a coupon to know you're getting the fair rate.
The chain of custody.
Solid-phase peptide synthesis in an ISO-certified US facility.
Reversed-phase HPLC to isolate the target compound above 99%.
Third-party lab runs identity (LC-MS), purity, endotoxin, and bioburden.
Insulated packaging, ice packs, transit monitoring, and lot-matched COA.
Questions before you buy? Read the FAQ.
Twenty-plus of the most common questions on shipping, storage, dosing math, legality, and returns — answered honestly.