my sheet has 4 lots from CPC with a spread under a point, which is tight
#test-results 2025-08-22
Friday33 messages6 participantstimes are UTC
Highlights from this day
- orfor_watch — posting my Medutest result on lot A-2601, what do people make of it 19:29
- blind_submit — the widest spread in my data is about 2.6 percentage points across five lots from one supplier 20:29
- blind_submit — sample handling on your end absolutely affects it. draw cleanly, ship fast, do not let it sit warm 20:31
- HPLC_Hank — whats the underfill rate people are actually seeing 21:11
- HPLC_Hank — if you are testing to settle an argument you will not settle it with n of 1 22:44
do the results in this channel skew because people test when suspicious
a result without a lot number and a purchase date is an anecdote with a pdf attached
a point or two between the certificate and an independent result is inside what two labs disagree by, we shall see
a result without a lot number and a purchase date is an anecdote with a pdf attached, not advice obviously
a supplier disputing a result is rare here and it has never gone well for the supplier
test it again
whats the lot
my read after three years of this: purity is mostly fine across the market and fill consistency is where suppliers differ
is it worth testing if the vial has already been through a warm transit
posting my Medutest result on lot A-2601, what do people make of it
anyone had a result they think was a lab error rather than a bad vial
the widest spread in my data is about 2.6 percentage points across five lots from one supplier
log the boring ones
👍1
the results in this channel skew because people test when they are suspicious. that is selection bias and it is real
i told HJ about a result they would not have liked and they did not argue. credit where it is due
how much does sample handling on my end affect the number
✅5
weigh the vial before you reconstitute. it costs nothing and catches the common failure
a single sample tells you about a single vial. that is genuinely all it tells you
what interests me is when the gap goes the same direction every time. once is noise, three times is a pattern, not advice obviously
log the lot number
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 / 10mgis quantity testing available as a separate thing or bundled
is a purity-only test worth the money if underfill is the common failure
the widest spread in my data is about 2.6 percentage points across five lots from one supplier
❤️6💀11
sample handling on your end absolutely affects it. draw cleanly, ship fast, do not let it sit warm
🔥1🎉16
if the vial has been through a bad transit you are testing the transit as much as the supplier
whats the underfill rate people are actually seeing
| Evidence | Counts? |
|---|---|
| Independent report, lot you bought, lot number legible | yes |
| Independent report, no lot number | no |
| Supplier certificate only | no |
| Screenshot of a report | no |
| Blinded pooled submission | yes, for the pool |
| A friend who said it was fine | no |
my result contradicts the supplier certificate, do i tell them
coming back after 20 months with a follow up result, where do i put it
[edited]do you test every order or sample it
nice result
i had a result i am fairly sure was a handling error on my side and i logged it as such
if you are testing to settle an argument you will not settle it with n of 1
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 / 10mgone data point
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 / 10mggenuine question i have never regretted spending the money on a test. i have regretted not testing twice