Abstract
A thin-layer chromatographic system comprising of silica gel as stationary phase and 1.0% aqueous urea solution as mobile phase (pH 7.44) has been developed for the mutual separation of five-component mixture of amino acids [lysine (R-F = 0.38), histidine (R-F = 0.59), leucine (R-F = 0.78), alanine (R-F = 0.87), and glutamic acid (0.98)]. The presence of foreign substances such as metal cations, anions, and vitamins as impurities in the sample on the separation was also examined. Thin-layer chromatographic parameters such as standard deviation (SD), Delta R-F, separation factor (alpha), and resolution (R-S) values of separated components of the mixture of these five amino acids were calculated. The limits of detection for lysine, leucine, and alanine were found to be 1.5 mu g spot(-1), whereas for histidine and glutamic acid, these were 1.2 mu g and 3.0 mu g spot(-1), respectively. The proposed TLC system is applicable for the identification and separation of amino acids in pharmaceutical formulations.