Seed-mediated strategy for synthesis of enzyme-encapsulated metal-organic frameworks with enhanced enzyme activity

Encapsulation of enzymes into metal-organic frameworks (enzyme@MOF) can improve the stability of enzymes. Most present synthesis methods of enzyme@MOF rely on the complex modification of enzymes or the natural negative surface charge of enzymes to promote the synthesis of enzyme@MOF. Despite extensive efforts, it remains challenging to develop a surface charge-independent and convenient strategy to encapsulate various enzymes into MOF efficiently. In this study, we proposed a convenient seed-mediated strategy for efficient synthesis of enzyme@MOF from the perspective of MOF formation. The seed, acting as nuclei, makes the slow nucleation stage skipped, leading to the efficient synthesis of enzyme@MOF. The successful encapsulation of several proteins demonstrated the feasibility and advantages of the seed-mediated strategy. Moreover, the resulting composite, cytochrome (Cyt c) encapsulated in ZIF-8, exhibited a 5.6-fold increase in bioactivity compared to free Cyt c. The seed-mediated strategy provides an efficient, enzyme surface charge-independent, and non-modified method for the synthesis of enzyme@MOF biomaterials, which warrants further exploration and application in diverse fields.