Sterility is not a percentage, which is the whole difficulty
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.
Fill & finish
Page 5 of 11 of this archive, newest first.
The fourteen-day problem, and what it does to a commercial testing model
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.
What twenty companies say about storage, and what they have measured
A stability programme needs a protocol, defined conditions, a stability-indicating method and time. Time is the ingredient no commercial testing service can sell.
How to read the silence on a certificate you already hold
Our position is about documentation practice. It is not an allegation about anybody’s honesty, and we are explicit about the difference.
Twenty-eight days is a number from somebody else’s product
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…
Why a dry powder is a chemical reactor with the volume turned down
Residual moisture is measured routinely in regulated manufacture, is reported almost nowhere in this trade, and predicts long-term stability better than any other single…
Same mass, different molecule: why identity by mass is not identity
Reversed-phase chromatography runs in an organic, acidic mobile phase that dissociates most non-covalent aggregates on the way to the detector.
Date of analysis, date of manufacture, and the gap between them
The interval between manufacture and analysis is the most under-read figure on the page, and the one most likely to matter by the time a vial is opened.
Reading a certificate as a document rather than as a score
The header identifies the batch, the table records the tests, and the footer says who is answerable. Two of the three are usually incomplete.
Hydrolysis, isomerisation, and the arithmetic of a broken bond
Deamidation, oxidation, aggregation and hydrolysis account for nearly all of what happens to a peptide over time. Each has a characteristic residue, a characteristic…
What we asked twenty suppliers about stability data
A retest date says that material should be re-examined before use. An expiry date says it should not be used. The trade uses the second word for the first concept.
Twenty-eight days is a number from somebody else’s product
Every degradation pathway accelerates by orders of magnitude on reconstitution, because the solvent that lyophilisation removed is the reagent most of them need.
Check the vial, not the box
What happens to traceability when bulk material is subdivided, repackaged and relabelled two or three times before sale.
Why JEEP can be entirely straightforward and still tell you nothing about bioburden
Purity, content, identity, sterility and endotoxin are five separate determinations. A single sheet of paper carrying one of them is not evidence about the other four.
Freezing a reconstituted vial: the ice-water interface problem
Every degradation pathway accelerates by orders of magnitude on reconstitution, because the solvent that lyophilisation removed is the reagent most of them need.
Sterility is not a percentage, which is the whole difficulty
Purity, content, identity, sterility and endotoxin are five separate determinations. A single sheet of paper carrying one of them is not evidence about the other four.
What the paperwork is for, and who it was designed to protect
The purity figure is the least informative line on a well-constructed certificate and the only line most buyers read.
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…
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.
A document, not a test: what a certificate actually is
The header identifies the batch, the table records the tests, and the footer says who is answerable. Two of the three are usually incomplete.