Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every quantitative result in a batch inherits the error of the standard used to calibrate it.
What I have: 98.2% · Janoshik · 97.9% · Medutest. I have used one of these for a while and I am considering switching, which requires a reason. What I care about is…
Concretely: ecnoglutide · a C4 column · mazdutide. I would like the axes of comparison first and the recommendation second. I have tried the first option and it…
The case in front of me: 98.4% · VendorInvestigate · 97.6% · Medutest. These are treated as interchangeable and I do not think they are. If both are acceptable I…
Numbers first: 99.4% · Janoshik · 98.2% · Medutest. I want to know what the trade-off actually is rather than which option is fashionable. I would rather have a…
The specifics, since they change the answer: 97.6% · PeptideMeter · 98.8% · Medutest. I am trying to choose between two options that are usually discussed as though…
The specifics, since they change the answer: 97.6% · PeptideMeter · 95.2% · Janoshik. I am trying to choose between two options that are usually discussed as though…
What I have: a TFA mobile phase · orforglipron · a C4 column. I can predict the outcome but I cannot explain it, which means I will get the next case wrong. I would…
Stated plainly: retatrutide · a C18 column · mazdutide. I suspect the honest answer is that it depends, in which case I would like to know on what. Assume I can…
What I am working with: 96.8% · Medutest · 97.9% · PeptideMeter. Both of these get recommended confidently by different people, which suggests neither is obviously…
Concretely: 97.9% · VendorInvestigate · 99.4% · Medutest. These are treated as interchangeable and I do not think they are. If both are acceptable I would like to…
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…
The specifics, since they change the answer: 98.8% · PeptideMeter · 97.6% · Janoshik. The comparison I want does not seem to exist anywhere in a form I can evaluate.…
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…
Concretely: 96.4% · VendorInvestigate · 99.4% · Janoshik. I would like the axes of comparison first and the recommendation second. I have tried the first option and…
What I am working with: retatrutide · a C18 column · cagrilintide. Both of these get recommended confidently by different people, which suggests neither is obviously…
The case in front of me: 97.6% · VendorInvestigate · 96.8% · PeptideMeter. These are treated as interchangeable and I do not think they are. If both are acceptable I…
The particulars: 95.2% · PeptideMeter · 98.8% · Janoshik. The comparison I want does not seem to exist anywhere in a form I can evaluate. I have read the arguments…
Setup, so nobody has to ask: 97.9% · Medutest · 98.8% · Janoshik. Both of these get recommended confidently by different people, which suggests neither is obviously…
Concretely: semaglutide · a C4 column · liraglutide. These are treated as interchangeable and I do not think they are. If both are acceptable I would like to know…
This is my second independent submission on material from the same supplier. This should be a straightforward calculation and I keep getting two different answers.…
I am comparing a supplier certificate against an independent result on the same lot. The units are where I keep going wrong, so please be explicit about them. I have…
Setup, so nobody has to ask: a formic acid mobile phase · cagrilintide · a wide-pore C18 column. The empirical answer seems settled. The explanation does not. If the…
The specifics, since they change the answer: 95.2% · PeptideMeter · 97.6% · Janoshik. The comparison I want does not seem to exist anywhere in a form I can evaluate.…
Stated plainly: 99.4% · Medutest · 96.4% · PeptideMeter. Both of these get recommended confidently by different people, which suggests neither is obviously right. My…
HPLC purity, identity confirmation and quantified content on the vial you actually hold. Reports arrive with the chromatogram attached, not just a number.
Submit a sampleFounded 1998. ISO 9001 and cGMP certified, 1,500+ staff and 200+ patents. The synthesis house behind a great many of the vials that get sent out for testing - batch-specific documentation with every order.
Visit GL Biochem