tions that took place after elution, the amount varied between 5 and 10 micrograms.By the combination of thin-layer chromatography with "in situ" microreactions or with reactions carried out after elution (without filtration), satisfactory results were obtained in the identification of 17 alkaloids with different composition and structure (the major compounds contained in opium, tropanic and beta-pyridinic derivatives, as well as lysergic acid). Microreactions "in situ" can also be applied for the obtention of standard substances, directly on the start line of the chromatoplate. LITERATURE CITED(1) I.

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