Cold Chain

Part 1 — Analytics

What twenty companies say about storage, and what they have measured

What would make a difference is not a regulator. It is three lines on a certificate, all of which are already known to whoever wrote it.

Part 2 — The Supply Chain

What the sequence tells you about how a peptide will fail

The sequence predicts the failure mode. A methionine predicts oxidation; an asparagine followed by a glycine predicts deamidation; a cysteine predicts disulphide scrambling.

Part 3 — Analytics

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.

Part 4 — The Supply Chain

What twenty companies say about storage, and what they have measured

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.

Part 5 — Analytics

One vial, four weeks, and the data that does not exist

Every degradation pathway accelerates by orders of magnitude on reconstitution, because the solvent that lyophilisation removed is the reagent most of them need.

Part 6 — The Supply Chain

Why a dead-clean sterile filter can pass pyrogen straight through

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.

Part 7 — The Supply Chain

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.

Part 8 — Laboratory Notebook

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.

Part 9 — Analytics

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.

Part 10 — Laboratory Notebook

Why TFC can be entirely straightforward and still tell you nothing about bioburden

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.

Part 11 — Analytics

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.