Dear Dr. Posz, we are currently working on a project to characterize various Euphrasia spp. chemically by HPTLC, and microscopically, to see if these species can be distinguished by chemical analysis. We are looking for additional samples of Euphrasia, in particular from Eastern Europe since this is where most of the commercial material is collected. In addition, we are interested in authenticated samples of Odontites species, since these are often sold labeled as "Euphrasia".

Please let me know if you are willing to help

Thank you so much for considering this

Stefan