Medutest result on a Xi'an tirzepatide lot lands 2.1 points below the supplier’s figure
The Journal submitted the sample and paid for the analysis. The vendor was told in advance.
Analytics in 2024
Page 2 of 10 of this archive, newest first.
Deamidation, oxidation, and the two shifts worth memorising
Deamidation adds 0.98 daltons. On a low-resolution instrument at incretin molecular weights, that is inside the noise.
VendorInvestigate result on a Guangzhou retatrutide lot lands 3.9 points below the supplier’s figure
The result is unremarkable. What the report omits is not.
Twenty-eight days is a number from somebody else’s product
Bacteriostatic water contains benzyl alcohol at 0.9 per cent, which inhibits microbial growth in a preserved multiple-dose presentation. It does not sterilise a contaminated…
The reviewer, the approver, and why regulated documents carry two names
What the Journal asks when a document arrives unsigned, and what the answers have been.
VendorInvestigate result on a Nantong cagrilintide lot lands 4.4 points below the supplier’s figure
The report states the gradient, the wavelength and the integration threshold, which is more than most.
The conservative convention: report the lower of two numbers
Aggregates dissociate in the mobile phase and are recorded as monomer. Only a size-based separation reports them.
Independent analysis puts a Homopeptide tirzepatide lot at 99.3%, against 95.3% on the certificate
The result is unremarkable. What the report omits is not.
Resolving power and mass accuracy are two different specifications
Calibration drift is real, unremarkable, and the reason serious laboratories run internal standards.
Independent analysis puts a SGN exenatide lot at 96.4%, against 94.7% on the certificate
The report states the gradient, the wavelength and the integration threshold, which is more than most.
Repackaging, subdivision, and the batch number that changed hands
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.
Independent analysis puts a QST dulaglutide lot at 95.3%, against 91.7% on the certificate
The result is unremarkable. What the report omits is not.
Independent analysis puts a TFC dulaglutide lot at 95.8%, against 95.1% on the certificate
The report states the gradient, the wavelength and the integration threshold, which is more than most.
The retest date and the expiry date are not the same document
A stability programme needs a protocol, defined conditions, a stability-indicating method and time. Time is the ingredient no commercial testing service can sell.
The shelf life ends when the diluent goes in
At low concentrations a measurable fraction of peptide can adsorb to glass and plastic surfaces, and the loss is largest exactly where it is least expected.
Independent analysis puts a ERP survodutide lot at 95.6%, against 92.3% on the certificate
A reminder that a purity figure is the output of a method, and that methods differ.
Janoshik result on a Shenzhen liraglutide lot lands 1.2 points below the supplier’s figure
The result is unremarkable. What the report omits is not.
Independent analysis puts a FGP exenatide lot at 96.3%, against 92.6% on the certificate
The supplier has not disputed the finding. It has not explained the gap either.
PeptideMeter result on a Guangzhou liraglutide lot lands 3.3 points below the supplier’s figure
The Journal submitted the sample and paid for the analysis. The vendor was told in advance.
How a release document is put together in a regulated plant
The header identifies the batch, the table records the tests, and the footer says who is answerable. Two of the three are usually incomplete.