How to run a thin-layer chromatogram

Prepare the TLC development tank using a clean, dry beaker, as shown in Fig. 32.11, and allow it to equilibriate for 10 minutes. 

Prepare the plastic backed TLC plate by drawing a fine line (the base line) in pencil about 1 cm above the bottom. Take care not to scrape off any of the stationary phase. Put three pencil dots on the base line - one in the centre and the others equidistant on either side, but no closer than 3 mm to the edges of the plate. 

3 Dissolve the mixture (1-3 mg) in two or three drops of a suitable volatile solvent (dichloromethane or ether are the most common), in a small sample tube. 

Is capillary action will draw the solution into the pipette. 

Touch the tip of the micropipette onto one of the pencil spots on the base line. Capillary action will draw the solution from the migropipette onto the plate as a spot. Do not allow the spot be mdre than 2 mm in diameter. Put the micropipette back into the sample tube containing the mixture. 

---