COLUMN CHROMATOGRAPHY

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COLUMN CHROMATOGRAPHY (CC)
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TLC - Optimizing for column chromatography
Optimum 0.2 lt Rf lt 0.5
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COLUMN CHROMATOGRAPHY
Column chromatography (CC) is an extremely
valuable technique for purification of synthetic
or natural products. Compounds are separated by
CC through the same mechanism as TLC
through differential intermolecular forces
between the components of the mixture with the
mobile phase, and between the components with
the stationary phase. A variety of adsorbents
can be used as the stationary phase
silica gel (which is very polar) is most commonly
used in organic chemistry.
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COLUMN CHROMATOGRAPHY
Polar components (b) adsorb more strongly to the
polar silica and elute after the less polar
components (a), which move more quickly with the
non-polar (relative to silica) solvent.
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COLUMN CHROMATOGRAPHY
Skoog and Leary Principals of Instrumental
Analysis, 4th ed. Suanders, 1992
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FLASH COLUMN CHROMATOGRAPHY
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FLASH COLUMN CHROMATOGRAPHY

• Build column
• Apply sample
• Elute
• Collect Fractions
• Analyze by TLC
• Combine pure fractions

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FLASH COLUMN CHROMATOGRAPHY
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FCC - OPTIMIZATION
Measure of column efficiency
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FCC Sample vs Column Size
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TLC vs High Performance Liquid Chromatography
(HPLC)
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TLC vs High Performance Liquid Chromatography
(HPLC)
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