ArticleKirchhoefer RD, Wells CE.
J Assoc Off Anal Chem. 1975 Sep;58(5):879-83.
Two semiautomated analytical systems have been developed to determine ergonovine and methylergonovine maleate in single tablets and injections. The active ingredient is dissolved in a tartrate buffer. In the fluorometric method the stream is automatically diluted with tartrate buffer and excited with ultraviolet light; the resulting fluorescence is measured and recorded. In the colorimetric method, the stream is automatically made basic with sodium hydroxide and extracted with n-butanol. The extract is mixed with p-dimethylaminobenzaldehyde reagent. After reaction, the solution is mixed with sodium nitrite solution, and the developed color is measured at 550 nm. Recoveries of 100% were obtained from spiked placebos. Standard deviations for powdered tablet and injection samples ranged from 0.63 to 1.24%. Comparisons with the USP XVIII methods are presented.