Page 54 - Applied Pharmacognosy
P. 54
Classification of Chromatographic Techniques
According to the Mode of Retention
1. Adsorption Chromatography.
What are the Factors affecting adsorption Chromatography ??
a. The affinity of functional groups of solute for the adsorbent.
• The affinity of functional groups for silica
in a decreasing order:
Amines (-NH2), carboxylic acids (-COOH), alcohols
O
O
-C-OH, amides -C-NH2, carbonyl -C=O, esters- C-OR,
ethers -C-O-C-, halocarbons -C-X, hydrocarbons -C-C-
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