looks re-dated
Thread · #coa-reading · 2026-03-28
the retention time on this one is different from
Spun off from a message in #coa-reading on 2026-03-28. 17 messages, 4 participants.
The message this came from
- void_volume — the retention time on this one is different from the last lot, problem 17:16
whats the minimum a certificate has to have before you take it seriously
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weigh the vial
not evidence on its own
update from 24 months ago: started asking every supplier for water content and about half now include it
the certificate from QYB is the one i use to teach this because it actually has a populated impurity table
why do some certificates report to one decimal and some to two
does purity by hplc at one wavelength miss things
whats the related substances table actually telling me
gross mass on a jewellery scale plus the water content is enough to catch most underfills
the three way match is vial, certificate, invoice. if all three agree you have something
what does net peptide content mean next to gross mass
why do some certificates report to one decimal and some to two
not detected means nothing
tfa counterion runs higher by mass than acetate. if the certificate does not say, you cannot do the mass balance
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comment_fatiguetfa counterion runs higher by mass than acetate. if the certificate does not say, you…
single wavelength detection can miss a co-eluting impurity that does not absorb there
sterility and endotoxin are separate tests and almost nobody runs either on research material