Biomimetic metal-organic frameworks mediated hybrid multi-enzyme mimic for tandem catalysis

The combination of chemo- and enzyme catalysis for multi-step tandem reactions has presented great challenges for decades. Herein, glucose oxidase (GOx) and a metal-organic framework MOF-545(Fe), which possessed peroxidase-like activity, were combined to construct a mimic multi-enzyme system for tandem catalysis. MOF-545(Fe) not only served as a support for the enzyme immobilization, but also contributed its catalytic activity to co-operate with natural enzymes for the cascade reactions. Based on the prepared mimic multi-enzyme system GOx@MOF-545(Fe), a colorimetric biosensor for glucose rapid detection was achieved with a low limit of detection (0.28 mu M) and high specificity. Meanwhile, due to the protection of MOF-545(Fe), the immobilized enzyme exhibited excellent reusability and stability, e.g. long-term stability, thermal stability and anti-organic solvent stability. After being stored at room temperature for 7 days, the immobilized enzyme retained 92% of activity, while only 40% of activity of free enzyme was retained. And the immobilized enzyme maintained 71% of its initial activity after 5 cycles. This strategy of combining MOF mimics and natural enzymes for tandem catalysis may provide a novel and facile approach to design a highly efficient, stable, functional chemo-enzyme composites catalyst, which holds great promise for applications in biosensing, biopharmaceutical and industrial catalysis.