ABSTRACT
The problems that face a biochemical engineer committed to designing a purification process, based on several chromatographic steps, are usually pragmatic and economical and related to such issues as throughput and recovery of adequately purified product, reproducibility, life length of adsorbent, hygiene, and convenience. Cleaning-in-place and sanitization-in-place designs and standard operating procedures for maintenance have to be developed and validated to ensure that the chromatographic capacity and selectivity are unchanged after each treatment. Hydrophobic interaction chromatography, for which salt promoted adsorption chromatography perhaps is a more relevant name, has become a major technique for process purification of proteins. In affinity chromatography, where by definition a biospecific ligand is used to obtain a high selectivity of binding, the main focus will be on the dissociation constant and the kinetics of binding. The basic phenomena that govern the behavior of proteins in chromatography columns are in principle independent of the scale of operation.
