VendorInvestigate result on a Shanghai mazdutide lot lands 2.8 points below the supplier’s figure
The supplier has not disputed the finding. It has not explained the gap either.
Félix Oyarzún
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Archive — page 4
134 piecesMedutest result on a Qingdao survodutide lot lands 2.7 points below the supplier’s figure
The Journal submitted the sample and paid for the analysis. The vendor was told in advance.
VendorInvestigate result on a Xianning cagrilintide lot lands 2.6 points below the supplier’s figure
The result is unremarkable. What the report omits is not.
Independent analysis puts a QYB dulaglutide lot at 99.3%, against 98.0% on the certificate
The report states the gradient, the wavelength and the integration threshold, which is more than most.
A vial can be 99.4 per cent pure and not sterile in the same afternoon
Every certificate circulating in this market answers a question about molecules. Almost none answers a question about organisms, pyrogens, or the integrity of the seal.
What PeptideMeter can tell you about a vial by weighing its water
The physics of the drying cycle explains why some cakes are matte and full-volume and others are glassy discs, and why the difference is not cosmetic.
Calibrated, qualified, accredited: three words that are not synonyms
An assay against a quantitative reference standard measures how much is present. Area per cent measures what proportion of the visible material is the parent. Only the first…
The cake tells you something, and it is not purity
Dye ingress and microbial immersion are probabilistic. Vacuum decay, high-voltage leak detection and helium mass spectrometry are deterministic and far more sensitive.
Independent analysis puts a CPC tirzepatide lot at 96.6%, against 92.7% on the certificate
A reminder that a purity figure is the output of a method, and that methods differ.
LAL, kinetic chromogenic, recombinant factor C: three ways to the same figure
We submitted vials for endotoxin determination and report the results, the method and the laboratory, because a pyrogen figure without a method is as empty as a purity…
Five lines that would change what a certificate is worth
None of what this piece asks for is commercially sensitive, and all of it is already known to whoever released the batch.
Independent analysis puts a ERP orforglipron lot at 97.4%, against 93.4% on the certificate
The report states the gradient, the wavelength and the integration threshold, which is more than most.
A few hundred participants carry the whole body-composition argument
What was pre-specified, what was exploratory, and what was calculated afterwards by people who did not run the trial.
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.
Five things a purity figure cannot tell you
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…
Deamidation, oxidation, and the two shifts worth memorising
What would be needed to catch each of these, and what it would cost.
Why Janoshik may run electrospray where another laboratory runs MALDI
The two ionisation techniques in general use produce different charge distributions, different adducts and different failure modes. Certificates almost never say which was…
PeptideMeter result on a Zhuhai mazdutide lot lands 2.7 points below the supplier’s figure
The result is unremarkable. What the report omits is not.
Nought point nine eight of a dalton: the modification that hides in plain sight
What would be needed to catch each of these, and what it would cost.
Janoshik result on a Suzhou semaglutide lot lands 0.7 points below the supplier’s figure
The result is unremarkable. What the report omits is not.