Hydrolysis, isomerisation, and the arithmetic of a broken bond
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.
Fill & finish
Aseptic filling, stoppering, capping, labelling and secondary packaging.
We asked four laboratories for a sterility test. Here is what came back.
Four independent services underpin confidence in this market. All four are competent at chemistry. Microbiology is a different accreditation, a different facility and a…
Two per cent water sounds like nothing and is not nothing
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…
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.
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.
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.
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.
LAL, kinetic chromogenic, recombinant factor C: three ways to the same figure
The limit for a parenteral product is calculable from the dose and the body weight in two lines. Almost nobody in this trade performs the calculation.
What we asked twenty suppliers about stability data
We asked twenty companies three questions about stability data and print every answer, refusal and non-response.
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.
One vial, four weeks, and the data that does not exist
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.
Two documents, two disciplines: purity and sterility are not the same trade
The Journal has read several hundred certificates from twenty companies. We set out what the documents actually cover, and what a reader is filling in from imagination.
Janoshik, Medutest, PeptideMeter, VendorInvestigate: a capability audit
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.
How a release document is put together in a regulated plant
Nothing on this page is difficult. It is simply unfamiliar, and unfamiliarity is what makes a weak certificate look like a strong one.
Benzyl alcohol is a preservative, not a sterilising agent
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…
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…
The retest date and the expiry date are not the same document
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.
Oxidation, and the peroxide that came in with the surfactant
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.
Low endotoxin recovery: the interference nobody looks for
The limit for a parenteral product is calculable from the dose and the body weight in two lines. Almost nobody in this trade performs the calculation.