Freeze-drying: primary and secondary drying, collapse temperature, the role of bulking agents and cryoprotectants such as mannitol and trehalose, and how to read a cake for evidence of a bad cycle.
The method section is present, which is unusual enough that I want to make use of it. I would like to know the limits of what can be inferred from this. What I am…
My setup is a refrigerator with a logger and a small work area I wipe down, nothing more. I want to know whether this is a real physical effect or an artefact of how…
I keep a written log of every draw with date, volume and syringe type. I want a method I can write down and repeat, not a rule of thumb. I would rather over-engineer…
I have accumulated enough vials from enough sources that the cakes now look wildly different from each other, and I have no framework for interpreting that. Examples…
I keep a written log of every draw with date, volume and syringe type. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not…
I have a logging thermometer, a box of insulin syringes and no illusions about my worktop being sterile. An unexpected observation, and I would like a differential…
Two things I want to understand properly rather than by rule of thumb. First: I keep reading that endotoxin survives autoclaving. Autoclaving is 121 degrees under…
Every supplier sheet I have says "store lyophilised powder at −20 °C for long-term, 2–8 °C for short-term, room temperature acceptable for shipping". Nobody explains…
I keep a written log of every draw with date, volume and syringe type. I want to understand what this actually establishes, as opposed to what it is being used to…
This is a recurring problem with one particular shipping lane rather than a one-off. I want to know whether this is a real physical effect or an artefact of how it is…
I have both a purity figure and a content figure, which is why the discrepancy is visible. I suspect the usual explanation for this is wrong, or at least incomplete.…
I have two vials of nominally the same compound from different suppliers. One cake is a dense white puck that sits proud in the vial; the other is a thin, almost…
I keep a written log of every draw with date, volume and syringe type. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not…
Transit was eleven days with two scanning gaps, so the thermal history is partly inferred. I would like the mechanism, because I want to be able to reason about the…
I keep a written log of every draw with date, volume and syringe type. I would like to understand the steps well enough to explain them to someone else. I have access…
I have both a purity figure and a content figure, which is why the discrepancy is visible. I am trying to choose between two options that are usually discussed as…
For context, I am working with a 10 mg presentation and a 2 mL fill. I noticed this today and I have not touched anything since, in case the state is diagnostic. I…
Analytical standards and reagents with traceable certificates. Every quantitative result you read inherits the accuracy of the standard behind it.
Shop standards