酵素在各種工業應用中廣泛使用，然而酵素在催化過程中容易失活且催化完後較難與產物分離，因此對於如何提升酵素穩定性就更顯得重要，而在眾多方法中酵素固定化是其中一個最有前景的方法。本實驗室在2015年時，第一個發展出以原位創新水相合成法，在溫和中性室溫環境中以類沸石咪唑骨架材料ZIF-90包覆過氧化氫酶，利用金屬有機骨架材料的孔洞性質把底物送入其中進行催化，也可以防止大分子蛋白質水解酶的作用，為酵素提供一個保護層。緊接著在2017又發表文獻對這種酵素複合材料做更進一步的探討，發現MOFs可以為酵素提供空間限制的效果，在變性劑尿素的情況下也能防止酵素反折疊而保持催化活性，為了更好地理解MOF中酶包封的機制，有必要研究用各種酶和MOF進行包封。然而，大多數MOF需要相對苛刻的合成條件，例如有機溶劑和高溫，這會破壞酶活性。因此探索製造MOF生物複合材料的替代途徑，以確保酶的存活，是一必要途徑。
如上所述，大多數酵素都是脆弱的，必須小心處理，以便它們能夠保持其功能，而機械化學合成方法提供了避免該問題的機會。首先，僅使用少量的溶劑可以最大限度地減少刺激性化學藥品對生物活性的潛在破壞作用；其次，快速反應時間使酵素暴露於反應條件最小化，這可以限制酶活性的損害，即使在對於在包封期間需要較少的原位合成也是如此，為此，我們對機械化學酶封裝進行了一項新的概念驗證研究。據我們所知，這項工作代表了使用此種方法的第一個例子，並且以此應用於兩種具有不同晶體結構的穩健MOF：UiO-66-NH2和ZIF-8。作為初始情況，β-葡萄糖苷酶分子成功地嵌入UiO-66-NH2和ZIF-8，並為了證明機械化學酶封裝策略的廣泛用途，我們進一步將研究擴展到比BGL更大和更小的酵素。

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.

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