update on the earlier thing i test roughly every tenth vial. it is a sampling strategy, not paranoia
i test roughly every tenth vial. it is a sampling strategy, not paranoia
#test-results 2026-03-04
Wednesday59 messages12 participantstimes are UTC
Highlights from this day
- assay_not_purity — nothing at all. and purity-only is the cheaper option so it is what most people buy and most vendors publish 19:21
- VialBot — new community result filed — vendor: Sangon Biotech · compound: tirzepatide · lot SGN-25-1129 · HPLC purity 98.6% · content 9.7 mg (10 mg label) · lab: Janoshik ·… 20:24
- one_variable — the answer is always you cannot separate them 21:01
98.6 against a certificate of 99.4 is fine. the same supplier landing low four times in a row is a question
underfill is more common than impurity. if you only test purity you are testing the less likely failure
my read after three years of this: purity is mostly fine across the market and fill consistency is where suppliers differ, i could be wrong
has a supplier ever disputed a result posted here
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 / 10mgnice result
one bad test does not condemn a supplier. one good test does not clear one. both halves get ignored equally
i have never regretted spending the money on a test. i have regretted not testing twice, i have it written down somewhere
post the lot, the purchase month, the lab, the number, and what you were expecting. that makes it useful later, ill dig out the number
if you are testing to settle an argument you will not settle it with n of 1, i could be wrong
selection bias
certificate said 96.8 and the independent came back 98.1, is that a problem
is anyone tracking results over time in a way they would share
the results in this channel skew because people test when they are suspicious. that is selection bias and it is real
does a bad result on one lot condemn the whole supplier
whats the lot
test it again
update from 14 months ago: retested the same supplier, result came back better, logged both
⚠️16📉8🧊5
follow up the widest spread in my data is about 2.6 percentage points across five lots from one supplier
what interests me is when the gap goes the same direction every time. once is noise, three times is a pattern
| 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 |
assay under label with good purity means you got less of the right thing. that is a fill problem, not a synthesis problem
log the lot number
coming back to this weigh the vial before you reconstitute. it costs nothing and catches the common failure
[edited]thats not great
📈3
thats a fill problem
a supplier disputing a result is rare here and it has never gone well for the supplier, n of 1 obviously
is quantity testing available as a separate thing or bundled
got my Janoshik report back and it is one page and i expected a novel
one or two pages is normal. what did you order
purity and quantity
then the page has everything you paid for. header with the sample code and date received, the test requested, the result, the method line, and the chromatogram
the two numbers people care about are the purity percentage and the mass figure. they come from two different measurements and it is worth understanding that they are independent
independent how
purity is the area ratio off the chromatogram.
quantity is the sample measured against a reference standard of that peptide at a known concentration.
you can pay for one, the other, or both.
the purity number does not feed the quantity number and vice versa
so a purity-only order tells me nothing about mg per vial
nothing at all. and purity-only is the cheaper option so it is what most people buy and most vendors publish
✅13
which is why the channel keeps saying content data is thin. it is not that nobody tests, it is that everybody buys the cheap test
and if you send a sealed vial they weigh it, which is the only way the mg number means the mg in your vial rather than the mg in your eppendorf
the report says the sample arrived as a sealed vial with intact cake. is that a standard line
they note the condition of what arrived. it is a small line and it has ended arguments in here
janoshik-J26-01844-sgn-tirz.pdf
2 pages · 176 KB · not retained in the public archive
that looks like a normal report. 98.6% and 9.7mg on a 10mg label is an unremarkable good result
unremarkable good is what i was hoping for honestly
turnaround for you?
posted on a monday, received the following tuesday, report four days later. so about twelve days door to inbox
that is a good run. two to four weeks is the range people should plan for, and december is worse
new community result filed — vendor: Sangon Biotech · compound: tirzepatide · lot SGN-25-1129 · HPLC purity 98.6% · content 9.7 mg (10 mg label) · lab: Janoshik · sample condition: sealed vial
second Sangon tirzepatide result on file and both over 98. still two
still two, yes. two is a hint
what would you not read into this report
do not read identity into it. a purity test with a matching retention time is consistent with tirzepatide, it does not confirm tirzepatide.
do not read sterility or endotoxin into it, those were not tested and are not offered as part of this.
do not read your other two vials into it either
the your other vials one catches everybody. one vial tested means one vial tested
the Wansheng lot i had done was 99.1 and the next vial from the same box, tested three months later, was 97.4. same box
storage difference over three months, or within-box variance, or method noise. take your pick, you cannot separate them
the answer is always you cannot separate them
😅11
because it is usually true. i would rather say it than pretend
how much did the pair of tests cost you all in
purity plus quantity plus postage has been in the same ballpark for a while, call it the price of a vial and a half. that is the honest exchange rate
which makes testing every order unrealistic
yes, and that is exactly why the pooled rounds exist. see #lab-requests