Abstract
Protein purification is an essential step after protein isolation. Protein
purification ensures the removal of all contaminants from the sample pool. Purification
depends on the chemical and physical interactions of protein molecules and chemical
moieties. These techniques are performed with tags and without tags. Tag purification
involves ammonium sulfate precipitation and dialysis. Purification of proteins with tags
utilizes affinity and size exclusion chromatography. There are various methods
available for this, however, we will discuss some most common methods for protein
purification.