180 J. A Asenjo and J B Chaudhuri relation to efficiency in a bioseparation. Some properties(e.g. charge and affinity)can show extremely high resolution in purification operations, whereas others(e. g. molecular weight) show much lower resolution 7.2 SYSTEM CHARACTERISTICS 7.2.1 Physicochemical basis for separation operations Development of new and efficient separation processes will be based on more effectively exploiting differences in the actual physicochemical properties of the product such as surface charge/ titration curve, surface hydrophobicity, molecular weight, biospecificity towards certain ligands(e.g. metal ions, dyes), pI and stability, compared to those of th contaminant components in the crude broth. The main physicochemical factors involved in the development of separation processes are shown in Table 7. 1(Asenjo, 1993) Table 7.1. Physicochemical basis for the development of separation processes ochemical basis Separation process Ion-exchange chromatography Electrodialysis Aqueous two-phase partitioning Reverse micelle extraction Hydrophobicity Hydrophobic interaction chromatography Reversed phase chromatography Precipitation Aqueous two-phase partitioning Specific binding Affinity chromatography Gel filtr Ultrafiltration lysis Electrophoresis Isoelectric point Chromatofocusing Isoelectric focusing Sedimentation rate Surface activity Adsorption Foam fractionation Solid-liquid extraction Supercritical fluid extraction From Asenjo, 1993)180 relation to efficiency in a bioseparation. Some properties (e.g. charge and affinity) can show extremely high resolution in purification operations, whereas others (e.g. molecular weight) show much lower resolution. 7.2 SYSTEM CHARACTERISTICS 7.2.1 Physicochemical basis for separation operations Development of new and efficient separation processes will be based on more effectively exploiting differences in the actual physicochemical properties of the product such as surface charge/titration curve, surface hydrophobicity, molecular weight, biospecificity towards certain ligands (e.g. metal ions, dyes), PI and stability, compared to those of the contaminant components in the crude broth. The main physicochemical factors involved in the development of separation processes are shown in Table 7.1 (Asenjo, 1993). J. A. Asenjo and J. B. Chaudhuri Table 7.1. Physicochemical basis for the development of separation processes Physicochemical basis Separation process Charge Ion-exchange chromatography Electrodialysis Aqueous two-phase partitioning Reverse micelle extraction Hydrophobicity Hydrophobic interaction chromatography Reversed phase chromatography Precipitation Aqueous two-phase partitioning Specific binding Affinity chromatography Size Gel filtration Ultrafiltration Dialysis Electric mobility Electrophoresis Isoelectric point Chromatofocusing Isoelectric focusing Sedimentation rate Centrifugation Surface activity Adsorption Solubility Solid-liquid extraction Foam fractionation Supercritical fluid extraction (From Asenjo, 1993)