Heterogeneous surface modification of hollow fiber membranes for use in micro-reactor systems

Development of the reversible PGA immobilization by using the immobilized metal ion affinity membrane

“…As seen in Table 2, the generally proposed methods for regeneration are to apply EDTA or imidazole as the stripping solution. Kroll et al [16] employed IMAM-Cu 2+ for green fluorescent protein (GFP containing His-tag) purification and up to 5 regenerations with only 85% residual activity retained when using EDTA as the stripping agent. Yang et al [8] applied immobilized metal ion resin with chelated Cu 2+ to form coordination bonds with bovine liver catalase (BLC).…”

“…On the other hand, EDTA was also employed for eluting the chelated metal ions from IMAM to reconstruct the metal ion affinity membrane [22]. Therefore, it was assumed that the regeneration process could be achieved by just applying the imidazole or EDTA as the stripping agents [16,22,23]. Accordingly, the effects of using imidazole or EDTA for IPM regeneration were tested and the results are shown in Fig.…”

“…However, organic solution was needed in the immobilization process to increase its stability [15]. Kroll et al have employed IMAM-Cu 2+ to adsorb green fluorescent protein in purification and only 85% residual activity was observed after 5 regenerations [16]; Yang et al used IMAC-Cu 2+ to coordinate bovine liver catalase and only 67% residual activity could be retained after 5 regenerations [8]. Scarce report concerned about the regeneration of supporting matrix to re-immobilize enzymes with successful results.…”

Polyethersulfone Hollow Fiber Membranes for Hemodialysis

“…Furthermore, many kinds of biomolecules, such as enzyme, protein and amino acid, could be covalently immobilized onto PES membranes by a simple chemical reaction. Kroll et al (Kroll et al, 2007) chemically modified commercially available PES and PSF hollow fiber membranes by reacting terminal hydroxyl groups with ethylene glycol diglycidyl ether (EGDGE) to produce terminal epoxy groups. For increasing loading capacity hydroxyethyl cellulose polymers were bound to the epoxy groups.…”

Development of a Novel Membrane Aerated Hollow‐Fiber Microbioreactor

“…Furthermore, those membranes can be tailor‐made (in terms of their molecular sieving properties and surface specificity using immobilized, ion exchange or affinity ligands) in order to be able to separate the products from the biocatalyst (4). A variety of methods to functionalize commercially available PES and PS membrane with different reactive ligands has been reported in many publications (10 − 12). Kroll et al (2007) successfully purified His‐tagged GFP from a clarified E. coli lysate using modified PES membranes, offering an alternative for the rapid capturing of His‐tagged protein in a bioreactor (12).…”