Colorimetric method for determination of corticosteroids by UV Visible Spectroscopy and its application to Ayurvedic formulations

Abstract

Usage of herbomineral preparations increased drastically these days. Some of the Ayurvedic formulations are been adulterated with steroids. Usage of such formulations can be injurious to health. Hence an attempt has been made to identify and determine steroids in both Ayurvedic and pharmaceutical formulations. In the present study a simple, sensitive and economical visible spectroscopic method has been used which involves the oxidation of corticosteroids by iron(III) and subsequent complexation of iron(II) with potassium  hexacyanoferrate (III), forming bluish green colored complex having the maximum absorbance at 780 nm. The method has been applied for the determination of corticosteroids in Ayurvedic formulations. The method has been statistically validated in which the  Standard deviation ranging  from  0.0008 to 0.0135,Relative standard deviation from 0.08% to 1.35% and Standard error was varying from 0.0018 to 0.0060 for selected Ayurvedic formulations. The studies have shown that the method is fast, reproducible and accurate and can be used in the analysis of marketed formulations. The processed samples were stable up to 2 hours minimizing the error in terms of fluctuating absorbance values.