TLC Introduction Chromatography is a physical method used to separate chemical mixtures into their distinctive constituents. The chemical mixture is allowed to dissolve in the fluid (mobile phase). The mobile phase carries a chemical mixture through a structure containing other packed material (stationary phase). Different components of the chemical mixture move at different speeds through the stationary phase, and this enables them to separate into characteristic chemical constituents. The separation of the mixture depends on the differential partitioning that exists between the stationary phase and mobile phase. The elusive differences in the partition coefficient of a particular compound lead to differential retention to occur on the stationary …show more content…
A line was drawn on the powdery surface of TLC sheet from one centimeter from the bottom using a pencil. 5 small spots (1cm between the spots and 1cm from the edges of TLC plate) were drawn on this line. The spots were marked as A, Ac, C, M, and U, starting from the first to the last spot. A, Ac, C, M and U represented aspirin, acetaminophen, caffeine, a mixture of the 3 analgesic drug ingredients and unknown analgesic drug respectively. The constituents of the analgesic drug were applied to the spots using the capillary tube. The fine capillary tube was dipped in an aspirin stock solution, and the two aspirin drops were quickly transferred to the spot marked A. This procedure was repeated for other analgesic drug components using different fine capillary tubes. A filter paper (9cm long) was placed against 400ml beaker wall. A 10ml ethyl acetate solution was transferred into the beaker by pouring an ethyl acetate solution down the filter paper; this step was performed in a hood chamber. The TLC plate was placed in an upright position with the marked line at the bottom, followed by covering the beaker tightly with a piece of aluminum foil. The solvent was permitted to rise up the thin-layer chromatography plate until it was one centimeter from the top of thin-layer chromatography plate. The TLC plate was removed, followed by immediately marking the solvent front. The TLC plate was allowed to dry up before it was