Enzymatic digestion followed by LC-MS/MS to confirm sequence rather than just mass. The method that catches a scrambled sequence or a D-amino-acid substitution that co-elutes and has the correct molecular weight.
I have both a purity figure and a content figure, which is why the discrepancy is visible. I suspect the usual explanation for this is wrong, or at least incomplete.…
For reference: 98.4% · survodutide. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an online calculator because…
The particulars: identity confirmation by mass spectrometry · aspartimide formation · a GLP-1 receptor agonist. The comparison I want does not seem to exist anywhere…
Setup, so nobody has to ask: 97.1% · mazdutide. I have worked this out and I would like someone to find the error, because I suspect there is one. My working so far,…
What I have: a sterility test · dimerisation · tirzepatide. I have used one of these for a while and I am considering switching, which requires a reason. What I care…
The specifics, since they change the answer: 97.9% · survodutide. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not…
Setup, so nobody has to ask: 98.8% · mazdutide. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked the order of magnitude…
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…
What I have: 97.1% · retatrutide. This should be a straightforward calculation and I keep getting two different answers. The numbers are arbitrary; the method is what…
Setup, so nobody has to ask: 96.8% · mazdutide. I have worked this out and I would like someone to find the error, because I suspect there is one. My working so far,…
The specifics, since they change the answer: 98.4% · semaglutide. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not…
Stated plainly: 96.4% · cagrilintide. I have worked this out and I would like someone to find the error, because I suspect there is one. My working so far, for the…
Stated plainly: 98.2% · a GLP-1 receptor agonist. I have worked this out and I would like someone to find the error, because I suspect there is one. My working so…
Conditions: 99.4% · oral semaglutide. Please show the division. I want to check my own against yours. I would like the general form as well as the specific number, so…
Details up front: 95.2% · dulaglutide. I can do the algebra. I am not confident about the conversion factors. If there is a standard way to lay this out, I would…
Stated plainly: 97.1% · cagrilintide. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked the order of magnitude and it…
Numbers first: 99.1% · orforglipron. I can do the algebra. I am not confident about the conversion factors. If there is a standard way to lay this out, I would rather…
The case in front of me: 99.1% · tirzepatide. I want the working, not the result — I need to be able to redo it with different numbers. I care about the precision as…
The particulars: 98.8% · semaglutide. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an online calculator…
Conditions: 97.9% · liraglutide. Please show the division. I want to check my own against yours. I would like the general form as well as the specific number, so I…
The particulars: peptide mapping · oxidation · cagrilintide. I am trying to choose between two options that are usually discussed as though only one exists. I am not…
For reference: 97.1% · survodutide. I would rather understand the derivation than memorise the outcome. Two people I asked gave two answers that differ by a factor of…
What I have: 98.8% · retatrutide. I can do the algebra. I am not confident about the conversion factors. If there is a standard way to lay this out, I would rather…
Numbers first: 95.2% · retatrutide. This should be a straightforward calculation and I keep getting two different answers. The numbers are arbitrary; the method is…
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