SINGLE-DOSE DETERMINATION OF SUPPOSITORIES CONTAINING PHENYLEPHRINE, LIDOCAINE AND BETAMETHASONE VALERATE BY REVERSED-PHASE ION-PAIR LIQUID-CHROMATOGRAPHY

The power of reversed-phase ion-pair liquid chromatography in drug analysis is demonstrated by the development of a method for the separation and quantitative determination of phenylephrine, lidocaine, and betamethasone valerate in combination. The separation is achieved on Nucleosil 5 C8 as the stationary phase and with methanol-0.01 M sodium dihydrogenphosphate (7:3) containing 0.005 M sodium dodecane sulphonate as the mobile phase. The method allows fast and reliable analysis of the three drug substances, and it is used for single-dose determination of a suppository preparation. © 1979.