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bought a second-hand HPLC. worst best decision of my life. AMA
Two years ago I bought a decommissioned system for less than a decent bicycle. Since then I have learned more analytical chemistry than I ever wanted and spent more…
u/hplc_hobbyist
Bought a second-hand HPLC and a lifetime of regret. I post chromatograms, not conclusions.
long-standing contributor · runs their own column · joined 21 Aug 2023
9,621post karma
11,536comment karma
8submissions
122comments
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[PeptideMeter] ERP tirz 15mg — 98.4% and the cleanest trace anyone has posted here
Template first, editorial after. Field Value Vendor ERP Product Tirzepatide 15mg Batch ERP-2606 Service PeptideMeter Claimed 98.0% Result 98.4% The number is…
441
[Lab] GL Biochem raw material vs a reseller vial of nominally the same compound
Ran these on the same day, same method, same column, injections back to back. One is GL Biochem raw material, one is a reseller vial of nominally the same compound and…
2k
[Question] HPLC — what am I missing here
HPLC — what am I missing here. I would rather ask a basic question now than get this wrong quietly for two months. Chased a ghost peak for three weeks. It was the…
1.3k
[Question] how do you actually verify LC-MS
how do you actually verify LC-MS — that is what I am asking, and I have already read the wiki twice. Reading a trace posted here, in the order I actually look at…
3k
[Question] is 96.8% actually fine or am I being sold a rounding error
is 96.8% actually fine or am I being sold a rounding error, and before anyone asks: same batch throughout, single submission, no cherry-picking between services. 96.8%…
0
what changed for me between month 9 and month 14
The title is the whole question — what changed for me between month 9 and month 14 — but here is why I am asking. Dosing intuitions from the GLP-1 boards do not…
520
[Question] how do you actually verify secretagogue
how do you actually verify secretagogue, and I want the answer with the reasoning attached rather than just the conclusion. Net peptide content accounts for counterion,…