Simultaneous assay of ephedrine hydrochloride, theophylline, papaverine hydrochloride and hydroxyzine hydrochloride in tablets using RP-LC.

The analytical problem was to control the quality of imported antiasthmatic tablets containing ephedrine hydrochloride, theophylline, papaverine hydrochloride and hydroxyzine hydrochloride. The aim of the analytical method for the assay was to separate, identify and quantify all compounds, at the same time. A gradient capable RP-LC system was used, using a commercially packed Nucleosil C18 column connected to a dual channel variable, programmable wavelength detector. The analysis was performed in the gradient program of increasing concentration of acetonitrile in water. The influence of pH of the mobile phase was established. The proposed method is reliable, reproducible, easy to perform and satisfies the aim.