How to dissolve ergosterol (Sigma) powder for the UPLC analysis (I am using C18 column with 98% methanol as the mobile phase) ?

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Yurii V Geletii

Why not to google?

https://pubchem.ncbi.nlm.nih.gov/compound/ergosterol#section=Solubility

https://www.researchgate.net/post/How-to-prepare-ergosterol-standard-for-HPLC-analysis

Kai Bester

I guess as always: take a volumemetric flask determine it weight, add ca 10 mg ergesterol, determine weight, fill up.

use this stock solution to make a dilution series. typically from 1 ng/L to 1 µg/L.... with say 7 concentrations points