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Sometimes elution of a TLC plate with one solvent does not achieve a good separation. How...

  1. Sometimes elution of a TLC plate with one solvent does not achieve a good

    separation. How could you elute the same TLC plate with two different

    solvents?

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Answer #1

There are many solutions:

  1. the most important is the 2-D (bidimensional) TLC : the TLC plate is developed with the first solvent, then it is dried and rotated 90º and it is developed with the second one.
  2. the bidirectional TLC: the TLC plate is developed with the first solvent, then it is dried and rotated 180º and it is developed with the second one.
  3. two solvent TLC: the TLC plate is developed with the first solvent, then it is dried and it is developed with the second one (same direction)..

There are a lot of details:

  • where to spot the samples
  • how different are the two solvents (e.g., the first one could be nonpolar and the second one polar)
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