Assay of Tretinoin using Safranine-O as a Chromogenic Reagent in Bulk and Dosage Forms

Abstract

A new, economical and accurate analytical technique was developed for the assay of tretinoin (TTN) in bulk and formulations. While developing the method, it was found that the reaction was carried out due to the formation of ion-pair association complex involving the carboxyl group in the side chain of the TTN with safranine-O. The colored species formined was stable up to 60 minutes. The optical density of color species was measured at 520 nm. All the variables were optimized. The linearity range lies for the developed method within the concentration ranges of 2-10 μg mL-1.The linear correlation coefficient (r) and molar absorptivity (ϵmax)values were found as 0.9999 and 1.66 x 104 L mol–1cm–1. Percentage recoveries were found from 99.2 ± 1.8 to 100.2 ± 0.7.The method was validated as per ICH guidelines.