Protein trap-engineered metal-organic frameworks for advanced enzyme encapsulation and mimicking

Immobilizing enzymes within metal-organic frameworks (MOFs) enables enzymes to against extreme environments. However, these MOF shells are just like armors, protective but heavy, which shield the enzymes from threats while locking them in the cage. The exploitation of immobilization strategy and intrinsic property of MOFs themselves is of great significance. Here, we proposed a functional protein trap strategy for efficient enzyme encapsulation. The ferrocenedicarboxylic acid (Fc) was used to induce the formation of defect-rich Co-based MOFs (CoBDC-Fc). As result, the engineered protein trap can not only improve the enzyme loading but also accelerate catalytic efficiency. Specifically, the atomically dispersed Fc sites serve as cocatalysts/cofactors and even change the conformation of enzymes in the construed microenvironment. Furthermore, the obtained CoBDC-Fc/enzyme exhibits excellent recyclability and tolerance to inhospitable conditions. Benefited by these, the CoBDC-Fc/enzyme/antigen composites were further prepared for cascade enzyme-linked immunosorbent assay of prostatespecific antigen with satisfactory sensitivity.

Automated summary

Immobilizing enzymes within metal-organic frameworks (MOFs) enhances their stability in extreme environments. This study proposes a functional protein trap strategy for efficient enzyme encapsulation. Utilizing ferrocenedicarboxylic acid (Fc) induces the formation of defect-rich Co-based MOFs (CoBDC-Fc), improving enzyme loading and catalytic efficiency. The engineered trap also exhibits excellent recyclability and tolerance to inhospitable conditions, enabling its application in enzyme-linked immunosorbent assay of prostatespecific antigen with satisfactory sensitivity.