1. Select a TLC tank that is large enough to hold the plate vertically and also be covered with a watch glass (cover).
2. Pour 2.5 mL of CH2Cl2 and 2.5 mL of hexanes into the TLC tank with containing a piece of 3 x 4 cm filter paper.
3. Obtain a UV active silica gel TLC plate that is approximately 1.5 cm wide and 5 cm long.
4. Make a small tick mark with a pencil for base line and solvent front as follow.
5. Dip the capillary tube into the known solution. The solution will rise in the tube, loading the capillary. Lower the capillary until it just touches the plate. The liquid will quickly flow out of the capillary making a visible circle. This is the origin for this compound and a second application directly on the same spot with the capillary. Again allow the solvent to completely evaporate.
6. Place the TLC plate vertically into the beaker, making sure that the spotting line does not dip into the solvent.
7. Leave the plate in the TLC tank until the solvent has advanced to the solvent front line and remove the plate from the TLC tank
8. Place the plate flat on the bench top and allow the solvent to completely evaporate. When the plate is completely dry, it is ready for visualization.
9. Place the plate under a UV lamp and trace the boundary of each spot with a pencil so that the shape of the tracing matches the shape of the spot.
10. Determine the Rf of your compounds.
11. Repeat steps 1-10 for two times but change the mobile phase to a mixture of acetone (1.5 mL): hexanes (3.5 mL) and a mixture of EtOAc (2 mL): hexanes (3 mL)