Determination of the content and purity of ergotamine preparations by means of high-pressure liquid chromatography.

A reversed-phase system of high-pressure liquid chromatography with solvent gradient is described for testing the purity of ergotamine as an active substance and for checking its concentration in pharmaceutical preparations. Because of its good resolution, this system can be used not only for the selective assay of ergotamine but also for the identification and quantitative determination, in the same chromatogram, of seven known isomerization and hydrolysis breakdown products. Simultaneous detection at two different UV wavelengths also makes it possible to measure further breakdown products formed by addition at the 9,10 double bond (lumi-compounds). The advantages of the system lie in the determination of all of the products within ca. 20 min, direct injection of low-dosage injection solutions and sensitive detection of polar breakdown products. The system is reproducible with regard to retention times and quantitative determination. It is suitable as a quality-control method for the routine determination of the content and purity of ergotamine preparations.