[Lab] 16th independent test on BCH, and the trend is the interesting part
I have had 4 orders now and I keep a table, so here is the honest summary rather than a vibe.
Material has been consistent. Communication has not. Shipping has varied by about 28 days on nominally the same lane, which matters more in summer than in February.
The independent number came back 96.8% against a claimed 97.2%, which I read as agreement rather than a discrepancy — inter-lab variance on this assay is a point or two either way and treating one lab as ground truth is how people end up in pointless arguments with vendors.
Batch number is in the comments. Ask if you want the method.
best — the order this archive was captured in
Strongly agree. Largest single impurity tells a different story than total purity.
Strongly agree.
Adding to this: integration is doing more work than the comment implies.
Mechanistically the bit that matters is method development. It explains most of the early profile and a decent chunk of the outcome.
chromatogram or it did not happen
I am going to push back on this slightly.
Detection wavelength? HPLC and that changes at different wavelengths.
Detection wavelength? chromatogram and that changes at different wavelengths.
This is the correct method framing. Column and gradient are load-bearing fields.
a round-robin on baseline integration would be genuinely useful
related substances are where the story lives, not the main peak
state the method: column, gradient, detection wavelength, injection volume
axis labels included, always
Slight fix: the number was 96.2, not 96.8. Decimal point, but a fairly consequential one.
the gradient is doing the separation work, not the column alone
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.
Not to be pedantic but gradient and chromatogram are being used interchangeably and they are not interchangeable in real life.
instrument quality is less important than analyst consistency
The evidence standard in c/vendorvetting gets called too strict about once a month, and every time, the thread ends with the complainant agreeing.
Sceptical. If this were true we would see it reflected in the data and we do not.
Inter-lab variance on this kind of assay is routinely 1–2 points. Different column, different gradient, different integration.
- 1Detection wavelength? chromatogram and that changes at different wavelengths.10 comments in this branch · started by u/rasmus_petrescu
- 2Strongly agree. Largest single impurity tells a different story than total…4 comments in this branch · started by u/micro_bump_mick