Identification and Quantitation of Corticosteroids and Their Esters in Pharmaceutical Preparations of Creams and Ointments by Thin-Layer Chromatography and Densitometry

Abstract

A rapid, simple, and specific thin-layer chromatographic (TLC) method is described for estimation of various corticosteroids and their esters when present in combination with other drugs in pharmaceutical preparation of creams and ointments. The cream or ointment is dissolved in chloroform; water and insoluble material, if any, are removed by centrifugation, and the steroid is separated from other ingredients by TLC on silica gel G with n-hexane as the first developing solvent (to wash out cream or ointment base) and chloroform–ethyl acetate (1 + 1 , v/v, for free steroids or 2 + 1 , v/v, for steroid esters) as the second developing solvent. The separated steroid or ester is visualized under shortwave UV (254 nm) and estimated by spectrodensitometry at 240 nm. Recoveries of the steroids are between 98.0 and 101.7%. Results were compared with those obtained by official methods, where applicable, and excellent agreement was found.

Pharmaceuticals and Related Drugs

“…A major review has appeared that discusses the methods and procedures used to analyze pharmaceutical and related compounds from November 1992 to October 1994 (). Likewise, other papers have considered more general topics such as regulatory issues related to standards and practices ( − ), validation ( − ), impurity analysis (), quality control (), and cleaning ().…”