Development of the extraction-photometric method for quantitative determination of Timolol Maleate

Abstract

The extraction-photometric method for quantitative determination of timolol maleate has been developed. This method is based on the ion associate formation with methyl orange dye; its chloroform solution has the absorption maximum at the wavelength of 426 nm. The method allows to determine the content of timolol maleate in the range of concentrations from 22.0×10-4 to 2.2×10-3 g/ml. During the work the reagents for forming the ion associate (0.1% solution of methyl orange, рН of phosphate buffer solution) have been selected. The stability of the chloroform solution of the ion associate has been studied. The following validation characteristics have been studied: robustness (the analytical solution is stable for an hour), linearity (a=-0.29% ≤ max a, 5.1%; b=1.0064; the correlation coefficient is 0.9992), accuracy (0.34% ≤ max δ, 1.02%), precision (1.13% ≤ max Δas 3.2%); they indicate the correctness of the given method for quantitative determination.