Mixed Surfactants enable separation of lysine from other essential amino acids in TLC on silica gel

Thin-layer chromatography of eight essential amino acids has been performed on silica layers with seventeen mobile phases of different composition. The mixed aqueous surfactant solution Triton X-100, 1.0 x 10(-5) M-sodium dodecyl sulfate, 8.1 x 10(-4) M-acetone 1:1:5 (v/v) was identified as the best mobile phase for specific separation of lysine. This separation can be successfully accomplished in the presence of impurities such as heavy metal cations, inorganic anions, and aliphatic and aromatic amines. The limit of detection of lysine was 0.5 mu g per zone. The method has been used for successful identification of lysine in Astymin (Forte) and Alamine (Forte) capsules.