one decimal versus two is usually just house style, not precision
#coa-reading 2025-12-13
Saturday13 messages3 participantstimes are UTC
Highlights from this day
- assay_not_purity — my 30mg vial weighed more than 2mg of powder, is the certificate lying 15:00
- assay_not_purity — if the certificate date precedes the lot date, ask. sometimes it is sloppiness and sometimes it is not 15:02
- assay_not_purity — single wavelength detection can miss a co-eluting impurity that does not absorb there 15:22
- panel_before_after — whats the related substances table actually telling me i asked SSA for the method and they sent it. that alone put them ahead of most 17:21
test it yourself
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why do some certificates report to one decimal and some to two
thats a tell
[edited]✅1
purity is not assay
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my 30mg vial weighed more than 2mg of powder, is the certificate lying
if the certificate date precedes the lot date, ask. sometimes it is sloppiness and sometimes it is not
| Line | Claims | Does not claim |
|---|---|---|
| Purity (area %) | fraction of detected material that is the target | how many mg are in the vial |
| Assay / content | mg of target per vial | that it is sterile |
| Water content | mass fraction that is water | anything about purity |
| Counterion | salt form and its mass share | net peptide unless stated |
| Related substances | what else was seen | what was not looked for |
single wavelength detection can miss a co-eluting impurity that does not absorb there
is a supplier certificate worth anything on its own
same chromatogram
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thats a real table
whats the related substances table actually telling me
i asked SSA for the method and they sent it. that alone put them ahead of most
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sloppy not sinister