Simple Overview of the 4 Common Techniques for Protein Purification
by Simon Currie, Ph.D.

by Simon Currie, Ph.D.
Proteins are the verbs of the cellular world. They perform important functions and carry out actions within our cells required for life itself. Over the years, scientists have coopted nature to leverage purified proteins as important tools in research, medicine, food and beverage, cosmetics and aesthetics, and chemical and environmental industries.
Proteins are purified in a few different ways, with distinct purification approaches solving unique challenges depending on the specific protein being purified and the application that it is being purified for.
Understanding the differences between each protein purification technique, and even knowing what the list of those techniques are can be a bit of a challenge.
Protein purification involves isolating a specific protein from a complex biochemical mixture such as cell lysate. A combination of affinity, ion exchange, hydrophobic interaction, and size exclusion chromatography steps are used to isolate a specific protein from the rest of the cellular milieu.
In this article we will take a broad look at these protein
purification techniques. The techniques summarized here also have links to
articles that dive deeper into why and how to conduct each specific type of
purification.
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