TLC-densitometric analysis of α-escin in bulk drug substance and in pharmaceutical dosage forms

A quite simple and rapid TLC-densitometric method for the identification of α-escin (Aescin) in bulk drug substances was developed. In so doing, different chromatographic conditions, including various mobile and stationary phases, were tested. A TLC densitometric determination of the examined compound was performed without using visualizing reagent, yet with the use of appropriate dipping reagents, in order to obtain reliable UV-densitometric measurements of α-escin - a substance which has weak chromophore groups. Herein, the application of a mobile phase containing n-butanolacetic acid-water in volume composition 30:7:13, the use of silica gel 60F₂₅₄ plates with concentrating zone, and subsequent application of 10% sulphuric acid in ethanol or 5% vanillin in methanol/sulphuric acid, respectively, provided the best results in a TLCdensitometric study of α-escin. The described method was successfully employed to identify α-escin in commercial samples that were in an oral dosage form (tablets) and also in the form of gel containing 20 mg of α-escin.