Spectrophotometric Determination of Corticosteroids and Its Application in Pharmaceutical Formulation

A simple, sensitive and economically viable spectrophotometric method for the determination of corticosteroids (predinsolone {PSL}, dexamethasone {DEX}, prednisone {PS}, betamethasone sodium phosphate {BEP} and hydrocortisone {HYD} has been developed. The method involves the oxidation of corticosteroids by iron (III) and subsequent complexation of iron (II) with potassium hexacynoferrate (III), forming bluish green colored complex having the maximum absorbance at 780 nm. The method has been applied for the determination of above-mentioned corticosteroids in pharmaceutical formulations. The common excipients do not interfere with the proposed method. A statistical comparison of these results with those of reported method shows good agreement and indicates no significant difference in the precision. The precision of the method developed is implied from the values of standard deviation which are varying from 0.03% to 1.06%. These are remarkable in comparison to the existing visible spectrophotometric studies on steroids. Marketed formulations of reported steroids have been analysed by calibration. Recovery experiments were found to be quantitative, and analysis to determine the mass per tablet was obtained with the variation of ±0.25% to 0.85% which implies the success of the method to get rid of the interference from excipients. 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 are also stable up to 2hours that minimizing the error in terms of fluctuating absorbance values.