Abstract

SIMULTANEOUS DETERMINATION OF BRIMONIDINE TARTRATE AND TIMOLOL MALEATE IN COMBINED PHARMACETICAL DOSAGE FORM USING TWO DIFFERENT GREEN SPECTROPHOTOMETRIC METHODS

Hiral S. Popaniya*, Mr. Hemant M. Patel

ABSTRACT

Two simple, rapid and precise UV spectroscopic methods namely Simultaneous equation (method 1), Q-absorbance ratio (method 2) and have been developed for the simultaneous determination of Brimonidine tartrate and timolol maleate. In method 1, both the drugs exhibit good linearity over the concentration range of 2-14 μg/ml and 5 to 35 μg/ml of Brimonidine tartrate and timolol maleate at 247.0 nm (r2=0.999 and 0.999 respectively) and 295.0 nm (r2=0.998 and 0.998 respectively) wavelengths respectively. Method 2, involves the formation of Q-absorbance equation using the absorptivity values at 266.0 nm (isoabsorptive point) (r2=0.998 and 0.998 respectively) and 295.0 nm (λmax of timolol maleate) (r2=0.999 and 0.998 respectively) and Beer’s Lambert’s law was obeyed over the concentration range of 2-14 μg/ml and 5-35 μg/ml respectively. The proposed methods were validated according to ICH guidelines for evaluation of accuracy, precision, sensitivity etc. In conclusion, the proposed methods are novel, simple, accurate, precise, sensitive, rapid and economically viable methods that do not require any prior separation procedure. The proposed two methods hold potential for simultaneous determination of Brimonidine tartrate and timolol maleate in ophthalmic formulation.

Keywords: Brimonidine tartrate, Timolol maleate, Spectrophotometric method, Simultaneous equation method, Q-ratio method, Validation.