An Improved Quantitative Thin–Layer Chromatographie Method Controlled by HPLC for the Determination of Ergotamine and Ergocristine in Crude Ergot

Abstract

A quantitative thin–layer chromatographic method based on the elution of the detected spots is demonstrated. The method is used for the selective determination of ergotamine and ergocristine, respectively in „ergotaminerich” and „ergocristinerich” ergot powders. A preliminary cleaning step of the plant extract is applied before chromatography and the TLC–separation is carried out on silica gel (pre–coated TLC–sheets Merck 5553) using chloroform – ethanol (9:1) solvent system. After UV–detection (365 nm) the appropriate spot areas are cut out from the sheet, followed by elution with a methanol – aqueous tartric (or phosphoric) acid mixture, and the absorbances of eluates are measured at 318 nm. Each step of the quantitative TLC method was controlled by HPLC. The coefficient of variation of the proposed procedure is less than + 2.5 %.

Key Word Index

Ergot - Quantitative TLC - Ergotamine - Ergocristin