i asked HJ for the method and they sent it. that alone put them ahead of most
#coa-reading 2026-01-15
Thursday21 messages6 participantstimes are UTC
Highlights from this day
- ghent_gradient — i asked HJ for the method and they sent it. that alone put them ahead of most 14:14
- deamidation — if you only read one line on a certificate, read the lot number. if you read two, read the assay 14:46
- deamidation — coming back to this whats the minimum a certificate has to have before you take it seriously 16:07
- two_lifts_a_week — mixed fonts and inconsistent kerning in one document is worth a second look 16:28
does purity by hplc at one wavelength miss things
quick one i was wrong about this for a year: area percent under-reports nothing, it just answers a different question than assay does
[edited]if you only read one line on a certificate, read the lot number. if you read two, read the assay
[edited]📈10🎉9👍14
weigh the vial
weights-monthly.csv
334 rows · not retained in the public archive
a certificate should name the method, the instrument, the column and the operator. most name none of those
thats a tell
nobody can authenticate a certificate from a scan. you authenticate the material by testing it yourself
should a certificate say which instrument and method they used
purity is what fraction of the contents is the target. assay is how many mg are actually there. different questions
one decimal versus two is usually just house style, not precision
coming back to this whats the minimum a certificate has to have before you take it seriously
❤️6🙏10💀1
Batch lookup B-0114: 6 independent reports on file, earliest 2025-11-05.
thats a real table
🧊2
i have never seen a research certificate with an endotoxin result on it. not once, happy to be corrected
[edited]certificate is dated before the lot date, is that just sloppiness
check the lot
single wavelength detection can miss a co-eluting impurity that does not absorb there, n of 1 obviously
mixed fonts and inconsistent kerning in one document is worth a second look
lot bought purity assay/label
A-2418 2025-03 99.1% 9.6 / 10mg
A-2601 2025-08 98.7% 9.8 / 10mg
B-0114 2026-01 99.3% 9.4 / 10mg
B-0329 2026-04 98.9% 9.9 / 10mgi keep every certificate in a dated folder and compare them. two suppliers had not changed their template since 2019
is endotoxin ever tested on research material