Integration of metal organic frameworks with enzymes as multifunctional solids for cascade catalysis
Enzymes exhibit a large degree of compatibility with metal-organic frameworks (MOFs) that allow to develop multicomponent catalysts constituted by enzymes adsorbed or occluded by MOFs. The combination of enzymes and MOFs in a multicomponent catalyst can be used to promote cascade reactions in which two or more individual reaction are performed in a single step. The cascade reactions take place due to the cooperation of active sites present on the MOF with the enzyme. Survey of the available data establishes that often the enzyme undergoes stabilization by association with MOF and the system exhibits a notable recyclability. In addition, the existence of a synergism is observed as consequence of the close proximity of all the required active sites in the multicomponent catalyst. After an introductory section describing the specific features and properties of enzyme-MOF assemblies, the main part of the present review focuses on the description of the cascade reactions that have been reported with commercial enzymes associated with MOFs, paying special attention to the advantages derived from the multicomponent catalyst. Related with the catalytic activity to metabolize glucose, generating reactive oxygen species and decreasing the solution pH, an independent section describes the recent use of enzyme-MOF catalysts in cancer therapy. The last paragraphs summarize the current state of the art and provide our view on future developments in the field.