Page 2 of 21 · 503 questions tagged hplc.
For reference: fibrillation · semaglutide · 4 °C. I understand the observation; what I do not understand is the mechanism behind it. I have read the two review…
What I have: Medutest · 96.8%. Before I write this off, I want to check whether it is a known failure mode. I have the lot number, the certificate and the date, and I…
This is my second independent submission on material from the same supplier. I would like the mechanism, because I want to be able to reason about the cases nobody…
For reference: 98.4% · ecnoglutide. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an online calculator because…
For reference: 98.2% · a wide-pore C18 column · a GLP-1 receptor agonist. I want to understand what this actually establishes, as opposed to what it is being used to…
Numbers first: 99.1% · list of related substances. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not looked at anyone…
Concretely: aspartimide formation · 37 °C. I want to know whether this is a real physical effect or an artefact of how it is measured. What prompted the question is…
Concretely: semaglutide · a C4 column · mazdutide. I would like the axes of comparison first and the recommendation second. I have tried the first option and it…
Setup, so nobody has to ask: dimerisation · a GLP-1 receptor agonist · minus 20 °C. The empirical answer seems settled. The explanation does not. If the honest answer…
Conditions: 99.1% · a C4 column · dulaglutide. I would like to know the limits of what can be inferred from this. What I am trying to avoid is over-reading a single…
Conditions: oxidation · liraglutide · 30 °C. This is one of those things that everyone repeats and nobody derives. This matters practically, not just academically,…
The specifics, since they change the answer: fibrillation · a wide-pore C18 column. I understand the observation; what I do not understand is the mechanism behind it.…
Setup, so nobody has to ask: HJ · an HPLC purity test. I want the working, not the result — I need to be able to redo it with different numbers. I care about the…
What I am working with: 96.4% · a C18 column · semaglutide. I have read the primary source rather than the summary, which has left me with more questions. I…
Numbers first: 98.8% · list of related substances. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not looked at anyone…
What I am working with: dimerisation · minus 80 °C. The empirical answer seems settled. The explanation does not. If the honest answer is that nobody knows, I would…
Conditions: aspartimide formation · liraglutide · 30 °C. I want to know whether this is a real physical effect or an artefact of how it is measured. What prompted the…
What I am working with: retatrutide · a C18 column · cagrilintide. Both of these get recommended confidently by different people, which suggests neither is obviously…
What I have: 97.1% · lot-specific certificate. This is presented as though it settles something, and I am not convinced it does. I have two documents that appear to…
The particulars: fibrillation · minus 80 °C. I understand the observation; what I do not understand is the mechanism behind it. I have read the two review articles…
Details up front: hydrolysis · minus 20 °C. I can predict the outcome but I cannot explain it, which means I will get the next case wrong. I would like to know how…
The case in front of me: an HPLC purity test · orforglipron. I would rather over-plan the first cycle and simplify later. I am prepared to do the work if someone can…
The specifics, since they change the answer: 98.4% · chromatogram. I want to understand what this actually establishes, as opposed to what it is being used to imply.…
The particulars: 98.8% · a wide-pore C18 column · a GLP-1 receptor agonist. I want to understand what this actually establishes, as opposed to what it is being used…