update from 16 months ago: started asking every supplier for water content and about half now include it
#coa-reading 2025-10-23
Thursday17 messages5 participantstimes are UTC
Highlights from this day
- underfill_uma — update on the earlier thing if you only read one line on a certificate, read the lot number. if you read two, read the assay 14:39
- salt_bridge — a certificate should name the method, the instrument, the column and the operator. most name none of those the honest summary is that a certificate tells you what the… 15:45
- two_four_ceiling — while im here does anyone actually check the residual solvents section 17:47
- two_four_ceiling — a supplier certificate on its own is a starting point, not evidence. that is the whole reason the verification channel exists, i think 17:48
update on the earlier thing if you only read one line on a certificate, read the lot number. if you read two, read the assay
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update on the earlier thing an identical chromatogram on two different lots is the single biggest tell there is
looks re-dated
is a supplier certificate worth anything on its own
i have never seen a research certificate with an endotoxin result on it. not once
a certificate should name the method, the instrument, the column and the operator. most name none of those
the honest summary is that a certificate tells you what the supplier says about a lot they chose to test
not detected means nothing
tfa counterion runs higher by mass than acetate. if the certificate does not say, you cannot do the mass balance, we shall see
water content is why an honest 10mg vial assays at 9.1. karl fischer titration, and most certificates omit it
is water content normally on a certificate or do you have to ask
check the lot
if the certificate date precedes the lot date, ask. sometimes it is sloppiness and sometimes it is not, from memory
certificate is dated before the lot date, is that just sloppiness
while im here does anyone actually check the residual solvents section
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a supplier certificate on its own is a starting point, not evidence. that is the whole reason the verification channel exists, i think
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the related substances table is the interesting part. a row of "not detected" means they did not look hard