#coa-reading 2025-09-22

water content is why an honest 10mg vial assays at 9.1. karl fischer titration, and most certificates omit it, n of 1 obviously

i keep every certificate in a dated folder and compare them. two suppliers had not changed their template since 2019

purity is what fraction of the contents is the target. assay is how many mg are actually there. different questions

a vial can be 99.4% pure and hold 8.1mg of a 10mg label. both numbers are true and only one of them is the one you care about

does purity by hplc at one wavelength miss things

for the archive my 15mg vial weighed more than 2mg of powder, is the certificate lying

the font on this one changes halfway down, am i being paranoid

not detected means nothing

ask for water content

residual solvents matter more than people think for anything that went through a lot of purification steps

is endotoxin ever tested on research material

same chromatogram

Reminder for apnoea_down_two: dose day is today. Set 6 days ago.

an identical chromatogram on two different lots is the single biggest tell there is

is sterility tested as part of a normal purity certificate

the retention time on this one is different from the last lot, problem

looks re-dated