Bioseparation Techniques and Their Applications
This chapter focuses on the primary methods used to extract, separate, and identify biologically important molecules. We have already covered methods used to separate proteins by one-dimensional and two-dimensional gel electrophoresis (sodium dodecyl sulfate-polyacrylamide gel electrophoresis [SDS-PAGE]) and to visualize them using silver and Coomassie blue stains in Chapter 3. In Chapter 5 and Chapter 6, we discussed how ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) are separated by agarose and polyacrylamide gel electrophoresis. In this chapter, we examine: (1) extraction methods for primary and secondary metabolites derived from microbial, plant, and animal cells; (2) purification methods for crude extracts prior to chromatographic separation; (3) chromatographic separation of organic molecules by adsorption chromatography, partition chromatography, and gel filtration or permeation chromatography; and (4) use of mass spectrometry (MS) and nuclear magnetic resonance spectrometry (NMRS) to identify biologically important molecules. We also include the very recent bioseparation techniques in use today. These include capillary zone electrophoresis and high-performance immobilized metal-ion affinity chromatography.