Synthesis and design of Nickel-Enzyme Ligand Framework for Catalytic Applications

Metal–organic frameworks (MOFs) are a versatile family of porous materials whose modular architecture enables tunable structural diversity and functional versatility. biological MOFs extend this concept by incorporating biomolecules as linkers, introducing biocompatibility and catalytic functionality. Here we performed the in situ construction of MOF elements through the direct involvement of enzymes during framework formation. In the absence of enzymes, Ni–MOFs exhibited a typical compact, closed morphology, whereas enzyme-assisted synthesis produced well-defined microsnowflake-like structures. The formation process was rapid, and extended synthesis times did not induce changes in the final morphology. Notably, the enzyme structure played a key role in determining the final architecture; the use of larger enzymes, such as catalase, resulted in the formation of a sandwich-like layered structure. Structural characterization confirmed the formation of a porous material with an average pore size of revealing an average pore diameter ranging from 3 to 6 nm and pore volumes between 0.17 and 0.22 cm³/g . Also Ni-ELFs hybrid showed surface area from 82 of m²/g to 139 m²/g (for Ni-ELF 1). Fluorescent labeling of the protein allowed the localization of the enzyme within the flake-like structures, revealing its preferential distribution at the periphery while leaving the central region accessible, thereby generating a novel hierarchical hybrid porous material. To evaluate catalytic efficiency, ELFs were tested in hydrolytic reactions as esterase/lipase-mimic catalysts. In this context, Ni-based ELFs outperformed free lipases with ELF-1 exhibiting the highest catalytic activity compared to other ELF hybrids. As a proof of concept for hydrolysis-mimic plastic degradation, ELF-1 demonstrated notable activity in the direct degradation of PET bottle fragments into microstructured products.