Characterization and comparison of hydrogels anchored with a tridentate, tetradentate and pentadentate chelators

摘要

Recent developments of new sorbents and metal chelation have increased the popularity of Immobilized Metal-Affinity Chromatography (IMAC). Investigation of alternative matrices such as hydrogels has led to identification of techniques that has the potential to overcome many of the disadvantages associated with packed bed chromatography such as low protein loading, elution conditions, regeneration and cost. The advantages support the use of these systems for development of large-scale purification application for industrial usage[1]. Since numerous neighboring histidine residues are uncommon among naturally occurring proteins for selectivity and isolation efficiency, it is important to develop systems that are efficient when there is a low number of histidine residues. Membrane chromatography is especially suited for large-scale processes and is based on the use of thin layers of finely organized and well-controlled macroporous polymeric stationary phases [1]. Due to the macroporous structure of the membrane support, membrane chromatography has lower pressure drops, higher flow rates, and higher productivity than column chromatography. The inclusion of immobilized metal affinity groups as fixed carriers in hyrodgel membrane matrices bound with a divalent metal enhances the separation characteristics of the membrane. Hydrogels are attractive materials as a chassis for the IMAC system due to its simple processability, biocompatibility and minor reactivity to environmental change (e.g. temperature, pH, etc.) [2].