Look up a lot number.

Every released lot is independently tested, and its certificate is published here as soon as the result returns. Enter the number printed on your vial — or on the label of a vial you are thinking of buying — and the certificate for that exact batch is returned.

Purity is measured by reversed-phase HPLC; identity is confirmed by mass spectrometry against the theoretical molecular weight. Certificates are published unedited, including lots that fall below specification and are withdrawn. Capitals, spacing and punctuation do not matter — rt202602 finds the same certificate as RT/202602.