A ZrO_xH_y-Templated UiO-66 Composite as a Heterogeneous Nanozyme for Site-Specific Myoglobin Proteolysis

Protein hydrolysis plays a crucial role in proteomics research, especially in disease mechanism studies, biomarker discovery, and drug target screening. However, existing natural enzymes still face challenges that prompt the development of more robust and tunable materials such as metal-organic frameworks (MOFs) that mimic the enzymatic hydrolysis reaction. In this work, we explore the modulation of the interaction between MOFs and proteins through surface modifications to achieve selective protein hydrolysis. We selected Zr-UiO-66 as an artificial nanozyme for myoglobin (Mb) hydrolysis as this MOF possesses excellent structural chemistry and catalytic activity, making it an ideal model system for studying MOF-mediated protein hydrolysis. To further tailor its surface chemistry, Zr gels synthesized by using the sol-gel process naturally possess surface hydroxyl groups, generating a hydrolytically active hybrid composite (Zr-UiO-66/tem), which has shown enhanced hydrolytic efficiency and protein adsorption specificity compared with the parent (Zr-UiO-66 particles). This study provides new insights into the development of efficient artificial proteases for the selective hydrolysis of proteins.