When a template becomes a misrepresentation
A PDF carries metadata about the software that produced it, and that metadata is frequently more informative than the content.
Fill & finish
Page 4 of 11 of this archive, newest first.
What Medutest charges to answer the pyrogen question
The masking phenomenon known as low endotoxin recovery means a formulation can return a clean result while containing endotoxin the assay cannot see.
Oxidation, and the peroxide that came in with the surfactant
Deamidation, oxidation, aggregation and hydrolysis account for nearly all of what happens to a peptide over time. Each has a characteristic residue, a characteristic…
Bacteriostatic water, sterile water, and the 0.9 per cent that makes the difference
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…
The cake tells you something, and it is not purity
Multiple-dose vials are designed for a defined number of punctures. Nobody counts, and the elastomer does not care whether anybody counts.
What Medutest would need in order to certify sterility, and why it does not
A compendial sterility test takes fourteen days of incubation and consumes the containers tested. That timescale is incompatible with the business model that made…
Aggregation: the impurity your chromatogram dissolved before it looked
We describe each pathway in enough chemical detail to explain why it is invisible to the method the trade uses, because that is the part which has practical consequences.
Why the independent testing market grew a chemistry arm and not a microbiology one
The absence of microbiological capability in this market is a commercial fact with a straightforward explanation, and it is worth understanding before blaming anybody for it.
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.
Asparagine, glycine, and the two residues that decide a shelf life
We describe each pathway in enough chemical detail to explain why it is invisible to the method the trade uses, because that is the part which has practical consequences.
Everything on the page, in the order a chemist would read it
The header identifies the batch, the table records the tests, and the footer says who is answerable. Two of the three are usually incomplete.
Everything on the page, in the order a chemist would read it
The header identifies the batch, the table records the tests, and the footer says who is answerable. Two of the three are usually incomplete.
What the four services actually offer, test by test
A compendial sterility test takes fourteen days of incubation and consumes the containers tested. That timescale is incompatible with the business model that made…
What VendorInvestigate would need in order to certify sterility, and why it does not
We asked all four services what they can determine, on what timescale, at what price, and under what accreditation. The answers are printed in full.
Asparagine, glycine, and the two residues that decide a shelf life
Deamidation, oxidation, aggregation and hydrolysis account for nearly all of what happens to a peptide over time. Each has a characteristic residue, a characteristic…
Bacteriostatic water, sterile water, and the 0.9 per cent that makes the difference
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.
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.
What a batch number is supposed to mean
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.
We asked four laboratories for a sterility test. Here is what came back.
A compendial sterility test takes fourteen days of incubation and consumes the containers tested. That timescale is incompatible with the business model that made…
What happens to a stopper after the fourth needle
Multiple-dose vials are designed for a defined number of punctures. Nobody counts, and the elastomer does not care whether anybody counts.