Thin-layer chromatography (TLC) has become a common and much favoured separation technique in laboratories in widely varied fields in recent years. Much of the credit for the introduction of this technique into analytical practice at the l 2 end of the 1950s is due to E. Stahl This method is simple and is characterized by high separation ability and sufficient sensitivity3; however, some analysts feel that it has passed the peak in its development and will gradually be replaced by the more modem high-performance liquid chromatography (HPLC). This is undoubtedly a very important analytical...