Who chose the vial that was tested?
Every third-party report in this market describes a sample somebody chose to send. That choice is outside the laboratory’s control and outside its records.
PeptideMeter
Page 6 of 8 of this archive, newest first.
Sending the same vial twice, under two names
Two years ago we ran an anonymised version of this comparison and promised a named one. This is it, with every method printed in full.
Set the threshold at a tenth of a per cent and the small impurities vanish
Baseline placement under a tailing peak is a judgement call with a direct effect on the area. It is one of the few places where two competent analysts genuinely disagree.
Six words a verification badge would need to mean anything
Every step between the laboratory report and the product page removes information, and the badge is the last step.
The named comparison we promised two years ago
The Journal submitted split samples from single lots to three assay services, under names unconnected to this publication, and published each method alongside each result.
Custody, condition and the temperature nobody logged
A result on one vial generalises to a batch only if the vial was drawn in a way that makes it representative — and nobody records how it was drawn.
Reproducibility, measured rather than assumed
The Journal submitted split samples from single lots to three assay services, under names unconnected to this publication, and published each method alongside each result.
The badge economy, and what it is actually certifying
Every step between the laboratory report and the product page removes information, and the badge is the last step.
Peak capacity, and the honest measure of a separation
Column chemistry, particle size and pore diameter determine what the separation is capable of before the gradient is even programmed.
The submitted sample: the weakest link in the whole system
A result on one vial generalises to a batch only if the vial was drawn in a way that makes it representative — and nobody records how it was drawn.
A tested vial is evidence about a vial
The condition on arrival is recorded by some services and not others, and it is one of the more informative lines in a report.
The badge is about a sample. The listing is about a product.
Every step between the laboratory report and the product page removes information, and the badge is the last step.
How a claim degrades between the bench and the listing
Every step between the laboratory report and the product page removes information, and the badge is the last step.
What orthogonal actually means, and what it does not
An orthogonal method separates on a different physical principle, so that species co-eluting in the first are likely to resolve in the second. Two runs of the same method at…
Six words a verification badge would need to mean anything
What a verification mark would have to carry to be checkable: a date, a lot, a method, a submitter and a link to the report.
From vial to bench: what is recorded and what is assumed
A result on one vial generalises to a batch only if the vial was drawn in a way that makes it representative — and nobody records how it was drawn.
We split six vials four ways and posted them
The Journal submitted split samples from single lots to three assay services, under names unconnected to this publication, and published each method alongside each result.
A peak with no chromophore is a peak with no peak
Non-chromophoric components — counter-ions, salts, some excipients — contribute mass to the vial and nothing at all to the chromatogram.
The badge economy, and what it is actually certifying
The Journal does not treat a badge as evidence and states so wherever it reports one.
How a claim degrades between the bench and the listing
What a verification mark would have to carry to be checkable: a date, a lot, a method, a submitter and a link to the report.