Immobilization in Layered Zirconium Phosphate and Phosphonate

A series of enzyme and proteins (met-myoglobin, lysozyme, met-hemoglobin, glucose oxidase, a-chymotrypsin) was also immobilized in a-ZrP by Kumar et al. [134]. Binding constant values clearly confirm the high affinity of the various proteins with the host structure (Table 15.4). 

Layered phosphate/phosphonate and phosphonate materials, obtained by substitution of the phosphate moiety by phosphonate groups, display interesting tunable hydrophilic/organophilic properties for adsorption processes. When Candida rugosa lipase (CRL) is simply equilibrated with zirconium phosphate and phosphonate [135,136], immobilization was demonstrated to take place at the surface of the microcrystals. However, because lipase exhibits a strong hydrophobic character, its uptake by zirconium phosphate and phosphonate was much more related to the hydrophobic/hydrophilic character of the supports than to the surface area properties. A higher uptake is observed for zirconium-phenylphosphonate (78 %) 

LiNa Geng et al. realized similar experiments for the adsorption of trypsin [141] and hemoglobin [142] on y-zirconium phosphate (y-ZrP) and organo y-ZrP intercalated with butylammonium (BA) and tetrabutylammonium (TBA). Hb adsorbed in the galleries of BA-y-ZrP and TBA-y-ZrP mainly by hydrophobic 

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