Page 125 - Applied Pharmacognosy
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Mobile Phase Selection

How to select the appropriate Mobile phase?

❑ Mobile phase selection is based on:      Polarity increases  Eluotropic series
   ➢ Relative polarity of the analytes.
   ➢ Column packing.                                              Petroleum Ether
   ➢ Compatibility with the detector in                        Carbon Tetrachloride
       hand.
                                                                    Cyclohexane
❑ Solvents for Normal Phase are mainly                                 Benzene
   nonpolar.                                                            Toluene

❑ Solvents for Reversed-Phase are                               Methylene chloride
   usually a mixture of water with polar                             Chloroform
   organic solvents such as acetonitrile.                            Diethyl ether
                                                                    Ethyl acetate
                                                                        Acetone
                                                                        Ethanol
                                                                       Methanol
                                                                          Water
                                                                      Acetic Acid 124
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