A vial can be 99.4 per cent pure and not sterile in the same afternoon
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.
Sterility
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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.
In-use periods, and the ones nobody can give you
Sharps disposal is a legal obligation in most jurisdictions and a safety obligation everywhere. Household waste is not a route.
A unit is not a dose, and it never was
Dead space in the needle hub is a real and calculable loss, and it matters more at small volumes than anybody expects.
What VendorInvestigate is able to certify about a sealed vial, and what it is not
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.
Four millimetres is enough, and the data says so
The insulin injection-technique literature is large, well conducted and directly transferable on questions of depth and tissue. We say where it stops transferring.
Priming a pen is not optional
For licensed products the in-use period is established by stability data. For a peptide reconstituted at home there is no such data, and the honest answer is that nobody…
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.
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.
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 a 1 mL syringe does that a 0.3 mL syringe does not
A unit is a volume. A dose is a mass. The bridge between them is concentration, and concentration is a number somebody has to calculate.
Gauge, pain and flow rate
Skin thickness at the standard injection sites is approximately two millimetres in adults and varies remarkably little with body mass. That single finding is why short…
How a correct calculation becomes a wrong dose
Almost every case involves a change — a new vial, a new syringe size, a new supplier — carried forward with an old number.
A unit is not a dose, and it never was
The graduation interval differs between barrel sizes, and a 1 mL barrel is frequently marked in two-unit steps. Reading one as though it were marked in single units halves…
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.
Why a dead-clean sterile filter can pass pyrogen straight through
Bacterial endotoxin is a heat-stable lipopolysaccharide from the outer membrane of Gram-negative organisms. It survives sterilisation, passes a sterilising filter, and is…
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…
Four millimetres is enough, and the data says so
The insulin injection-technique literature is large, well conducted and directly transferable on questions of depth and tissue. We say where it stops transferring.
Mapping a rotation that you will actually follow
A rotation scheme that is too complicated will not be followed. We describe the simple ones that are.
Units, millilitres, milligrams: three scales on one small object
We work through the arithmetic in full, because it is short, and because the errors it prevents are order-of-magnitude errors.