Assay versus purity: why the two numbers are not interchangeable
A 98% assay and a 98% purity can describe two very different drums. The difference is what the other 2% is.
November 14, 2026
Technical notes
Short notes on the parts of a route that decide whether a building block is usable: assay, isomeric ratio, impurity fate, storage and the arithmetic behind a scale-up.
Storing alkynes, aldehydes and acetals: what actually degrades and how fast
Three functional groups, three different failure modes, and one habit that prevents most of them.
November 14, 2026
Gram to kilo: the four things that change when a route is scaled
Heat transfer, addition rate, work-up time and the impurity that was invisible at a gram. None of them show up in a yield calculation.
November 14, 2026
How to read a building block COA without skipping the part that matters
Identity, assay, impurity profile and water content say four different things. Most buyers check the second one and stop there.
November 14, 2026