Principles of protein purification

The  main  goal  in  protein  purification   is  to  isolate  one  exacting  protein  of interest from other contaminating proteins so in which its structure and/or other characteristics can be studied. Formerly a suitable cellular source of the protein has been recognized, the protein is liberated into solution and then separated from contaminating  material  through  sequential  use  of  a  series  of  various  fractionation  methods  or partitions.  These partitions exploit one or more of the following basic properties of the protein that are as follows:  its solubility, its size, charge, hydrophobicity or exact binding affinity.  These  divide  may  be  chromatographic  methods  like  as  ion  replace,  gel  filtration  or hydrophobic   interaction   chromatography,   affinity chromatography  in   that   the protein connect to a hydrophobic  material or electrophoretic  methods  like as isoelectric focusing. Other electrophoretic procedures, primary sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE), are used to monitor the extent of puri?cation and to determine the molecular mass and subunit composition of the purified protein.