Building a shared glossary: HPLC, LC-MS, lyophilised, COA

Half the confusion I see from newcomers is vocabulary, not science. Proposing we keep a running plain-English glossary. I'll start:

COA — certificate of analysis, the test report for a specific batch.

HPLC — high-performance liquid chromatography; separates components so you can read a purity percentage.

LC-MS — liquid chromatography paired with mass spec; confirms the molecule's mass.

Lyophilised — freeze-dried to a powder/cake for stability.

Add yours below and I'll fold them into a tidy post.

Adding: reconstitution — dissolving a lyophilised powder in a diluent (often bacteriostatic water) to make a liquid stock at a known concentration. The whole job is mass ÷ volume.

Useful thread — folding two in: lot/batch number , the identifier tying a vial to its specific COA; and reference standard , the known-identity material an assay is compared against. We'll cite these in the pinned COA reference.

Please add area percent : the proportion of total chromatogram peak area attributed to the main peak. It is not the same as weight percent and I will not stop saying so.

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