Analysis of some steroids by thin-layer chromatography using optimum mobile phases.

The aim of this paper was the analysis of five androstane isomers by thin-layer chromatography (TLC). The choice of proper mobile phase and the optimization of the mobile phase composition are very important because the chromatographic separation is difficult to achieve. In the first step, the proper mobile phase system was chosen from seven elution systems presented in the literature using numerical taxonomy method. The proper solvent system was found to be the mixture of chloroform, acetone, and petroleum ether. In the second step the composition of mobile phase was optimized by "simplex" method and "prisma" method. The optimum TLC system can be applied for the separation of androstane isomers from real samples such as drug formulation, biological and natural sources.