Simultaneous Determination of Cinnarizine and Dimenhydrinate in Binary Mixture Using Chromatographic Methods

Two accurate and sensitive chromatographic methods have been developed and validated for simultaneous determination of cinnarizine (CIN) and dimenhydrinate (DIM). The first method uses simultaneous quantitative thin layer chromatography (TLC) spectrodensitometric evaluation of them, using ethyl acetate:methylene chloride (8 : 2 by volume) as a mobile phase. Chromatograms are scanned at 254 nm. This method analyzes CIN in a concentration range of 0.5-6 µg per band with mean percentage recovery of 99.78 ± 1.001 and DIM in a concentration range of 1-6 µg per band with mean percentage recovery of 99.87 ± 1.319. The second method is high-performance liquid chromatography using methanol:acetonitrile:water [85 : 10 : 5, by volume +0.5% tri ethyl amine (TEA)] as a mobile phase. The linearity was found to be in the range of 10-60 and 5-60 µg mL(-1) for CIN and DIM, respectively. The methods were successfully applied to the simultaneous determination of CIN and DIM in bulk powder, laboratory-prepared mixtures and pharmaceutical dosage forms. The validity of results was assessed by applying standard addition techniques. The results obtained are found to agree statistically with those obtained by a reported method, showing no significant difference with respect to accuracy and precision.