Janoshik result on a Qingdao semaglutide lot lands 3.7 points below the supplier’s figure
A reminder that a purity figure is the output of a method, and that methods differ.
Recent work
107 piecesThe badge is about a sample. The listing is about a product.
A badge asserts that something was tested. It does not assert what, when, on whose sample, by what method, or whether the lot on sale is the lot that was tested.
How far back does this document actually reach?
A document is only as good as the chain that connects it to the material, and most chains here are two or three links longer than the paperwork admits.
Who signed this, and what did they undertake by signing it
Somebody has to be answerable for a release document. On most certificates in this market, nobody is named at all.
Why a dead-clean sterile filter can pass pyrogen straight through
The masking phenomenon known as low endotoxin recovery means a formulation can return a clean result while containing endotoxin the assay cannot see.
VendorInvestigate result on a Guangzhou retatrutide lot lands 4.2 points below the supplier’s figure
The result is unremarkable. What the report omits is not.
Janoshik, Medutest, PeptideMeter, VendorInvestigate: a capability audit
Endotoxin is the more tractable of the two questions, and a kinetic chromogenic determination is neither slow nor exotic. It is simply not on the menu.
A certificate is a snapshot, and peptides do not stand still
A document is only as good as the chain that connects it to the material, and most chains here are two or three links longer than the paperwork admits.
Janoshik result on a Hangzhou cagrilintide lot lands 0.9 points below the supplier’s figure
The Journal submitted the sample and paid for the analysis. The vendor was told in advance.
Independent analysis puts a MKM dulaglutide lot at 98.2%, against 96.7% on the certificate
The report states the gradient, the wavelength and the integration threshold, which is more than most.
Independent analysis puts a MKM cagrilintide lot at 97.3%, against 95.9% on the certificate
The supplier has not disputed the finding. It has not explained the gap either.
Deamidation is the commonest degradation route and the hardest to see
An isoaspartate rearrangement changes the molecule and not the mass. A method that confirms identity by molecular weight alone will report it as the parent compound.
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.
PeptideMeter result on a Guangzhou exenatide lot lands 4.3 points below the supplier’s figure
The result is unremarkable. What the report omits is not.
The header, the table and the signature block
The header identifies the batch, the table records the tests, and the footer says who is answerable. Two of the three are usually incomplete.
Quadrupole, time-of-flight, orbital trap: what each class can and cannot see
Calibration drift is real, unremarkable, and the reason serious laboratories run internal standards.
A certificate is a snapshot, and peptides do not stand still
What happens to traceability when bulk material is subdivided, repackaged and relabelled two or three times before sale.
Who signed this, and what did they undertake by signing it
A manufacturer’s certificate is a self-declaration. An accredited laboratory’s report is a third-party measurement. The trade prints both under one heading.
Freezing a reconstituted vial: the ice-water interface problem
An in-use period is established by a dedicated study on a specific formulation in a specific container at a specific concentration. Borrowing one from a marketed product is…
Independent analysis puts a JEEP mazdutide lot at 98.9%, against 97.7% on the certificate
The Journal submitted the sample and paid for the analysis. The vendor was told in advance.