Living organisms are enormously complex. Proteins are fundamental for executing a wide variety of life controlling functions.
Proteins are of high interest both in the academic community as well as within the pharmaceutical industry, as malfunctioned proteins are often associated with causes of disease. Diabetes is a well-known example (insulin). By understanding the function/malfunction of proteins we can find possibilities to develop medicines to cure diseases.
The most common methods for preparative purification of proteins all involve chromatography. The method separate according to differences between the properties of the protein to be purified (the target protein) and the properties of other substances in the sample.