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