Twelve minutes or forty: what gradient slope buys
A shallow gradient resolves impurities that a steep one runs into the parent peak. Both methods are legitimate; only one of them can see the small stuff.
Janoshik Analytical
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Why a result on one vial says less than the trade needs it to
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 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.
Custody, condition and the temperature nobody logged
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.
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…
Two gradients, one sample, two purities
A shallow gradient resolves impurities that a steep one runs into the parent peak. Both methods are legitimate; only one of them can see the small stuff.
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.
Why a result on one vial says less than the trade needs it to
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.
What a split-sample exercise can establish, and what it cannot
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.
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.
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.
What competing on one number does to a market
A market that competes on one measurement will optimise that measurement. There are legitimate ways to raise a purity figure that involve no change to the product at all.
From vial to bench: what is recorded and what is assumed
The condition on arrival is recorded by some services and not others, and it is one of the more informative lines in a report.
From vial to bench: what is recorded and what is assumed
What a laboratory can and cannot know about the provenance, storage history and representativeness of what lands on its bench.
How a claim degrades between the bench and the listing
The Journal does not treat a badge as evidence and states so wherever it reports one.
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.
A tested vial is evidence about a vial
What a laboratory can and cannot know about the provenance, storage history and representativeness of what lands on its bench.
Three services, one lot, and a spread of two and a half points
Duplicate submissions under different names test within-laboratory repeatability, which is a different quantity from between-laboratory reproducibility.