How to Read What You’re Looking At
A certificate is only useful if you know what each line is actually saying. Here’s the honest version.
The purity percentage — what is it really counting?
The lab runs the sample through HPLC, which separates it into every component it contains and measures each one. The percentage is simple arithmetic on that result: how much of what the instrument saw was the stated peptide. 99.0% means 99.0% of the detected signal was the target compound — and 1.0% was something else, reported rather than rounded away.
Why the CAS number is on here
A CAS Registry Number belongs to exactly one chemical structure — there are no shared numbers and no close-enoughs. Paired with the lab’s identity testing, it documents that the material in the vial is the stated molecule itself, not a cousin with a similar profile. High purity of the wrong compound would be worthless; this line is what rules that out.
What an endotoxin line reports
Endotoxins are bacterial residues (lipopolysaccharides) that can turn up in any biologically produced material. Labs quantify them with the LAL assay and state the result in endotoxin units (EU) against the reporting threshold they used. When a certificate here carries an endotoxin figure, that is this lot’s measured level — we show it when the lab measured it, and we don’t invent it when they didn’t.
The batch number is the whole point
A certificate speaks for one batch of material — the one the lab physically received — and no other. The batch or lot number is the thread that ties document to vial: the number on your label should match the identification number on this page. If it doesn’t, you’re reading the wrong certificate, and we’d rather you notice than assume.
Why we sometimes test one lot at two or three labs
Different laboratories run different instruments, methods and calibrations, and none of them answer to us. When independent labs land on consistent numbers for the same lot, each report backs up the others — that agreement is worth more than any single figure. Every certificate on this page names the lab that issued it, so you always know whose work you’re reading.
Does a clean certificate mean this is approved for human use?
No. A Certificate of Analysis reports the chemical identity, purity and measured properties of one research lot — nothing more. Everything sold on this site is for in vitro laboratory research use only, not for human or animal use of any kind.