Page 138 - phytochemistry general program
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Modes of Paper Chromatography
1. Preparative Paper Chromatography .1
Using either several sheets of paper or custom-made preparative card-boards. .2
.1
Positions of the bands are indicated either : .2
Non-destructively for colored materials or by UV light for fluorescent materials,
Destructively by spraying with the proper reagent of either guide spots (or edge .1
.2
spray technique).
2. Multiple chromatography
Multiple chromatography includes all procedures in which the development is
repeated.
Multiple development
The chromatogram is repeatedly developed in the same direction, which leads to
complete separation of the mixture components whose Rf values are close.
One can use either the same or different solvent systems.
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