Original Articles: 2011 Vol: 3 Issue: 1
Simultaneous RP HPLC determination of Latanoprost and Timolol Maleate in combined pharmaceutical dosage form
A simple, fast and precise reverse phase high performance liquid chromatography method is described for simultaneous determination of latanoprost and timolol maleate using methyl paraben as an internal standard. Chromatographic separation of these two drugs was achieved on Waters symmetry C18 column (250 mm x 4.6 mm, 5 μm) as stationary phase with a mobile phase comprising of 0.05% (v/v) trifluoro acetic acid in water : 0.05% (v/v) trifluoroacetic acid in acetonitrile (40:60 v/v) at a flow rate of 1ml / min and UV detection at 210 nm. The retention time of timolol, maleic acid, methyl paraben and latanoprost were 1.967 min, 2.342 min, 3.275 min and 7.633 min respectively. The proposed method was validated for system suitability, linearity, accuracy, precision, LOD, LOQ and solution stability. Linearity, accuracy and precision were found to be acceptable over the ranges of 2.5 – 7.5 μg/ml for latanoprost and 250 – 750 μg/ml for timolol maleate. It can be conveniently adopted for routine quality control analysis.