Summary Table of Chromatography Component Phases
This is called the baseline
Place a spot of pure reference compound on the left of this line, then a spot of the sample to be analysed to the right of the baseline and allow to air dryThe reference compounds will allow identification of the mixture of compounds in the sample
The solvent will begin to travel up the plate, dissolving the compounds as it does
As solvent reaches the top, remove the plate and draw another pencil line where the solvent has reached, indicating the solvent frontThe sample’s components will have separated and travelled up towards this solvent front
A dot of the sample is placed on the baseline and allowed to separate as the mobile phase flows through the stationary phase; The reference compound/s will also move with the solvent
Rf =
Rf values can be calculated by taking 2 measurements from the TLC plate
The baseline on a TLC plate must be drawn in pencil
Any other medium would interact with the sample component and solvents used in the analysis process.
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