Figure 12.6. Column Chromatography
Sample is added to the top of the column, and a solvent is poured over it. The more similar the
sample is to the mobile phase, the faster it elutes; the more similar it is to the stationary phase, the
more slowly it will elute (if at all).Eventually, the solvent drips out of the end of the column, and the different fractions that leave the
column can be collected over time. Each fraction will contain different compounds. After collection,
the solvent can be evaporated, leaving behind the compounds of interest. Column chromatography
is particularly useful in biochemistry because it can be used to separate and collect macromolecules
such as proteins or nucleic acids. There are several techniques that can be used to isolate specific
materials, which are described in the following paragraphs, as well as in Chapter 3 of MCAT
Biochemistry Review.