integration vs purity — genuinely asking which matters more
Long-ish post, sorry. tl;dr at the bottom.
I have been tracking LC-MS against eGFR for 15 weeks because I could not find anyone who had. The correlation is weaker than I expected, which is itself mildly interesting given how confidently people link the two in here.
Caveats up front: one person, one lab, one assay, no control, and I changed my training in the middle of it, which was stupid.
tl;dr: probably real, definitely smaller than the threads imply, and not worth reorganising your week around.
best — the order this archive was captured in
The related substances profile is way more interesting than the main peak %. A 98% with 12 peaks is different from a 98% that is one 34% impurity.
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This is the correct method framing. Column and gradient are load-bearing fields.
Strongly agree. Largest single impurity tells a different story than total purity.
Did they post the raw trace or just the summary?
The related substances profile is way more interesting than the main peak %. A 98% with 13 peaks is different from a 98% that is one 34% impurity.
Slight fix: the number was 98.7, not 98.9. Decimal point, but a fairly consequential one.
The related substances profile is way more interesting than the main peak %.
Disagree on that part. 95.1% and 93.7% on the same vial is normal.
Did they post the raw trace or just the summary?
integration decision on a shoulder changes your number by half a point on its own
integration decision on a shoulder changes your number by half a point on its own
Adding to this: method development is doing more work than the comment implies.
state the method: column, gradient, detection wavelength, injection volume
- 1Strongly agree. Largest single impurity tells a different story than total…9 comments in this branch · started by u/chain_confirm_c
- 2The related substances profile is way more interesting than the main peak %.…4 comments in this branch · started by u/hana_lehtinen