In: Chemistry
1. Besides silica and alumina, can any other stationary phases be utilized for the separation of chlorophylls?
2. Predict the order of compounds on a TLC for the b-carotene, chlorophyll a and b, and cryptoxanthin pigments found in spinach. Also, predict the order of elution from the column. Explain/justify your answer with polarity arguments.
1. depending upon the compound you want to seperate different stationry phases on TLC are used . commercially available TLC stationary phases are silica gel, alumina, cellulose, bonded phases, polyamide,etc.., .since silica gel is highly polar in nature most of the compounds can be sepated using it.so it is widely used.
2. order of compounds on TLC from top to bottom is
b-carotene, chlorophyll-a, chlorophyll-b , xanthophyll
elution strength :perfluoroalkane (weakest), hexane, pentane, carbon tetrachloride, benzene/toluene, dichloromethane, diethyl ether, ethyl acetate, acetonitrile, acetone, 2-propanol/n-butanol, water, methanol, triethylamine, acetic acid, formic acid (strongest).