| dc.description.abstract | In spite of widely used in diverse industrial applications, enzymes suffer from stability and recyclability problems owing largely to their relatively easy deactivation and the difficulty of post-catalytic separation, respectively. Several techniques have been developed to enhance the robustness of enzymes and to provide a heterogeneous environment for easy separation. However, the immobilization of the enzyme on a solid support represents a particularly promising method. In our previous report in 2015, we proposed a highly efficient way of encapsulating the enzyme of catalase in Zeolitic Imidazolate Framwork-90 (ZIF-90) under aqueous named de novo approach which is capable of protecting the embedded enzyme from protease and maintaining its biological activity. Lately, our group published a report in 2017 further showed that MOFs can provide spatial confinement to enzymes so that enzymes could still have functionalities even with the participation of denaturing agents. To investigate and gain more knowledge in the area of confinement, we need more examples composed by vary MOFs with different enzymes. Most of the MOFs, however, require relatively harsh synthetic conditions such as organic solvents and high temperatures along with long reaction time. Comparing synthetic conditions for demanding survival to most enzymes, it is thus important to explore an alternative route to fabricate MOF biocomposites.
As mentioned above, enzymes usually are fragile and need to be handled with attention. In this context, a mechanochemical method provide certain advantages for this regard. First, the use of only a trace amount of solvent and precursors that could minimize the potential detrimental effects on biological activity. Additionally, a rapid reaction time allows those enzymes to expose to external surrounding with less time in order to yield enzymes more opportunity to survive and present good biological activity. To this end, we have performed a new proof-of-concept study using a mechanochemical method to encapsulate enzymes in MOFs. This is the first example of a mechanochemical biomineralization method using trace amounts of solvents as our knowledge. We applied our approach to two robust MOFs with different crystal structures: zeolitic imidazolate framework-8 (ZIF-8) and University of Oslo-66 with amino moieties (UiO-66-NH2). β-glucosidase (BGL) molecules were successfully embedded in ZIF-8 and UiO-66-NH2 to demonstrate the broad utility of the mechanochemical enzyme encapsulation strategy. To demonstrate the broad utility of the mechanochemical enzyme encapsulation strategy, we further extended our study to enzymes both larger and smaller than BGL. | en_US |