Describe the methods for separating macro molecules on the basis of
molecular size, solubility and molecular affinity.
The methods for separating macromolecules on the basis of:
* molecular size: gel-filtration chromatography (proteins are less soluble in solutions containing high salt than they are in low-salt solutions; so that a mixture of proteins can potentially be separated by addition of large quantities of a salt);
* solubility: salting out (macromolecules interact either with positively or negatively charged stationary phase);
* molecular affinity: affinity chromatography (chromatographic column is set up for which the stationary phase contains a functional group that interacts specifically with the protein of interest).