Estimation of Dorzolamide and Timolol in Eye Drops by a RP-HPLC Method

A rapid, simple, accurate and economic High Performance Liquid Chromatographic analysis method has been developed for simultaneous estimation of Dorzolamide Hydrochloride (HCl) and Timolol Maleate in eye drop dosage forms is highly desirable to support formulation screening and quality control. The chromatography system used a reversed phase with C-18 column. The sample was analyzed using methanol: 1-octane sulphonic acid buffer, in the ratio of 55:45 as a mobile phase at a flow rate of 1.0 ml/min and detection with UV/Visible detector at two fixed wavelength (254.0 nm for Dorzolamide HCl and 295.0 nm for Timolol Maleate). The concentrations of these drugs were evaluated in marketed formulation by using simultaneous method. The present book describes the simultaneous estimation method of Dorzolamide Hydrochloride and Timolol Maleate in eye drop dosage form. The simultaneous estimation method given good recovery (accuracy), precision, linearity. Hence the method successfully used for quality control and routine analysis of drugs in eye drops dosage forms